JEE (MAIN+ADVANCED)

PERIODIC PROPERTIES
 CONTENT

S.No Pages

1. Periodic Properties 02 – 36
2. Exercise-1 37 – 63
3. Exercise-2 (Objective Questions) 64 – 85
4. Exercise-3 (Section-A) 86 – 88
5. Exercise-3 (Section-B) 89 – 90
6. Exercise-4 91 – 96
7. Answer Key 97 – 108
 PERIODIC PROPERTIES

PERIODIC PROPERTIES
CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES
Need for classification:
It is verydifficult to studyindividuallythe chemistryof all the elements and millions of their compounds,
hence to simplify and systematize the study of chemistry of the elements and their compounds, they are
classified into groups and periods. Early attempt to classify the elements:
Classification of Lavoiser
Elements had been classified into two major groups by Lavoiser
1. Metals 2. Non–metals
This classification was based on the differences in their properties.
Metals Non-Metals
(i) They are hard but not brittle (i) They are soft and brittle
(ii) They are very good conductor of (ii) In general they are not good
heat and electricity conductors of heat and electricity
exception : Graphite
(iii) They are having good quality of (iii) No “ Lustrous” property.
“lustre”
(iv) They are sonorous. (iv) No such sonorous property.

Dobereiner’s law of triads:

It was first attempt towards classification. He arranged similar elements in a group of three elements
called triad and the atomic mass of the middle elements of the triad is approximately the arithmetic
mean of the other two.
e.g. Ca40 Sr87.5 Ba137
137  40
At. wt. of Sr =  88.5
2
88.5 is nearly similar to 87.5 of atomic wt. of Sr.
Such a group of elements is called Dobereiner’s triad.
Newland’s law of octaves:
When the lighter elements are arranged in order of their increasing atomic weights, then every eight
element is similar to the first element in its properties, similarly as the eight node of a musical scale
is similar to 1st one. e.g. Na 8th element resembles in its properties with Li. Similarly K the 8th
element from Na and so on.
Name of element Li Be B C N O F
7 9 11 12 14 16 19
Name of element Na Mg Al Si P S Cl
23 24 27 28 31 32 35.5
 This type of classification was limited up to only 20 elements.
 Inert gas element were not discovered till then.
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 PERIODIC PROPERTIES

Lother Meyer arrangement: Cs

Rb
K
Br
Na

Atomic Volume
Ca
Li Cl
Sr I
Ba
F
Be
Mg

Metalloid and transition metals

Atomic Weight

 The graphs plotting the atomic volumes against atomic weights are known as Lother Meyer volume
curves.
 The alkali metals have highest atomic volumes along their respective periods.
 Alkaline earth metals (Be, Mg Ca, Sr, Ba, etc.) which are relatively a little less electropositive, occupy
positions on the descending part of the curve.
 Halogens and the occupy positions on the ascending part of the curve.
 Transition elements have very small volumes and therefore these are present at the bottoms of the curve

Exercise
Lother Meyer attempt was based on plotting atomic mass vs
(1)Atomic size (2)Atomic volume (3) Density (4) Melting point
Ans. 2

MENDELEEV’S PERIODIC LAW

(i) Mendeleev’s Periodic Law - The physical and chemical properties of elements are the periodic
function of their atomic weight

(ii) Characteristic of Mendeleev’s Periodic Table -

(a) It is based on atomic weight

(b) 63 elements were known, noble gases were not discovered.

(c) 7 Horizontal rows are called periods.

(d) Vertical columns are called groups and there were 8 groups in mendeleev’s Periodic table.

(e) Each group upto VIIth is divided into A & B subgroups. ‘A’sub groups element are called normal
elements and ‘B’ sub groups elements are called transition elements.

(f) The VIIIth group consisted of 9 elements in three rows (Transition metals group).

(g) The elements belonging to same group exhibit similar properties.

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 PERIODIC PROPERTIES

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 PERIODIC PROPERTIES

MODIFIED MENDLEEV'S PERIODIC TABLE OF ELEMENTS

(iii) Merits or advantages of Mendeleev’s periodic table -
(a) Study of elements - First time all known elements were classified in groups according to their
similar properties. So study of the properties of elements become easier.
(b) Prediction of new elements - It gave encouragement to the discovery of new elements as some
gaps were left in it. Sc (Scandium), Ga (Gallium), Ge (Germanium),Tc(Technetium) were the elements
for whom position and properties were defined by Mendeleev even before their discoveries and he
left the blank spaces for them in his table.
e.g.:Blank space at atomic weight 72 in silicon group was called Eka silicon (means properties like
silicon) and element discovered later was named Germanium.
Similarly other elements discovered after Mendleev's periodic table were.
Eka aluminium - Gallium (Ga) Eka Boron - Scandium (Sc)
Eka Silicon - Germanium (Ge) Eka Manganese - Technetium (Tc)
(c) Correction of doubtful atomic weights - Correction were done in atomic weight of some elements.
Atomic Weight = Valency × Equivalent weight.
Initially, it was found that equivalent weight of Be is 4.5 and it is trivalent (V = 3), so the weight of Be
was 13.5 and there is no space in Mendeleev’s table for this element. So, after correction, it was
found that Be is actually divalent (V = 2). So, the weight of Be became 2 × 4.5 = 9 and there was a
space between Li and B for this element in Mendeleev’s table.
– Corrections done in atomic weight of elements are – U, Be, In,Au, Pt.
(iv) Demerits of Mendeleev’s periodic table -
(a) Position of hydrogen - Hydrogen resembles both, the alkali metals (IA) and the halogens (VIIA) in
properties so Mendeleev could not decide where to place it.
(b) Position of isotopes - As atomic weight of isotopes differs, they should be placed in different
position in Mendeleev’s periodic table. But there were no such places for isotopes in Mendeleev’s
table.
(c) Anomalous pairs of elements - There were some pair of elements which did not follow the
increasing order of atomic wts. eg. Ar and Co were placed before K and Ni respectively in the
periodic table, but having higher atomic weights.
 Ar K   Te I   Co Ni   Th Pa 
       
 39.9 39.1 127.5 127   58.9 58.6   232 231 
(d) Like elements were placed in different groups.
There were some elements like Platinum (Pt) and Gold (Au) which have similar properties but were
placed in different groups in Mendeleev’s table. Pt – VIII,Au – IB
(e) Unlike elements were placed in same group.
st
I group

IA IB
Li
Na
More reactive K Cu Less reactive
Alkali metal Rb Ag Coin metals
Normal elements Cs Au Transition element
Fr
– Cu,Ag andAu placed in Ist group along with Na, K etc. While they differ in their properties (Only
similar in having ns1 electronic configuration)
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 PERIODIC PROPERTIES

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 PERIODIC PROPERTIES

MODERN PERIODIC LAW

 Mosley proved that the square root of frequency () of the rays, which are obtained from a metal on
showering high velocityelectrons is proportional to the nuclear charge of the atom. This can be represented
by the following expression.
 = a (Z–b) where Z is nuclear charge on the atom and a and b are constants.

 The nuclear charge on an atom is equal to the atomic number.

 According to modern periodic law. “The properties of elements are the periodic functions of their atomic
numbers”

Exercise
Which of the following expressions is correct ?
(1) ν = a(z–b) (2) ν2 = a (z–b)2 (3) ν = a2 (z–b)2 (4) ν2 = a2 (z–b)2
Ans. 3

Cause of periodicity: It is due to the repetition of similar outer shell electronic configuration at a
certain regular intervals.
Structural features of the long form of the periodic table.
On the basic of the modern periodic law, a scientist named Bohr proposed a long form of periodic
table that was prepared by Rang and Warner.
(i) It consists of 18 vertial columns called groups and 7 horizontal rows called
periods.
(ii) Elements of groups, 1, 2, 13 – 17 are called normal or representative elements.
(iii) Elements of groups 3 – 11 are called transition elements.
(iv) The 14 elements with atomic numbers (Z) = 58 – 71 (occurring after lanthanum 57La in the
periodic table) are called lanthanides or rare earth elements and are placed at the bottom
of the periodic table. The 14 elements with atomic numbers (Z) = 90 – 103 (Occurring after
actinium 89Ac in the periodic table) are called actinides and are also placed at the bottom
of the periodic table.
(v) The Eleven elements with Z = 93 – 103 (93Np – 103Lr) which occur in the periodic table
after uranium and have been prepared from it by artificial means are called transuranics.
These are all radioactive elements.
(vi) The elements belonging to a particular group are said to constitute a chemical family which
is usually named after the name of the first element. For example, Boron family (group 13),
carbon family (group 14), nitrogen family (group 15), and oxygen family (group 16). In addition
to this, some groups have typical names. For example,
Elements of group 1 are called alkali metals
Elements of group 2 are called alkaline earth metals
Elements of group 16 are called chalcogens
Elements of group 17 are called halogens
Elements of group 18 are called zero group or noble gases.
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 PERIODIC PROPERTIES

The long form of the periodic table contains seven periods. These are :
1st period (1H – 2He) contains only two elements. This is the shortest period.
2nd period (3Li – 10Ne) and third period (11Na – 18Ar) contain 8 elements each and are
called short periods.
4th period (19K – 36Kr) and 5th period (37Rb – 54Xe) contain 18 elements each and are
called long periods.
6th period (55Cs – 86Rn) contains 32 elements and is the longest period.
7th period (87Fr –) is, however, incomplete and contains at present only 24 elements.
In yet another classification, the long form of the periodic table has been divided into four
blocks (i.e., s, p, d and f ), depending upon the subshell to which the last electron enters.

MERITS OF LONG FORM OF PERIODIC TABLE OVER

MANDELEEV’S PERIODIC TABLE
 Positions of Isotopes and Isobars - Isotopes have same atomic number and the periodic table is
based on atomic numbers. Therefore, various isotopes of the same elements have to be provided the
same position in the periodic table. Isobars have same atomic weights but different atomic numbers and
therefore they have to be placed at different positions.
 The position of actinides and lanthanides is more clear now because these have been placed in IIIB
groups and due to paucity of space, these are written at the bottom of the periodic table.
 In the periodic table a diagonal line from B toAt separates the metals, nonmetals and metalloids from
one another. The elements like B, Si,As, Te,At, that are situated near this line are metalloids i.e. these
have characteristic of both metals and nonmetals.
 The general electronic configuration of the elements remains same in group.

DEFECTS OF LONG FORM OF PERIODIC TABLE

 The position of hydrogen is still disputable as it was there in Mendeleev's periodic table in group IAas
well as IVA & VIIA.
 Helium is an inert gas but its configuration is different from that of the other inert gas elements
 Lanthanide and actinide series could not be adjusted in the main periodic table and therefore they had to
be placed in a separate block below the periodic table.

CLASSIFICATION IN BLOCKS
s-block elements.
Elements of groups 1 and 2 including He in which the last electron enters the s-orbital of the valence
shell are called s-block elements. There are only 14 s-block elements in the periodic table.

p-block elements.
Elements of groups 13–18 in which the last electron enters the p-orbitals of the valence shell are called
p-block elements.
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d-block elements.
There are three complete series and one incomplete series of d-block elements. These are: 1st to
3d - transition series which contains ten elements which atomic numbers 21–30 (21Sc – 30Zn).
2nd or 4d-transition series which contains ten elements with atomic numbers 39 – 48 (39Y – 48Cd).
3rd or 5d transition series which also contains ten elements which atomic numbers 57 and 72 – 80
(57La, 72Hf – 80Hg).

4th or 6d transition series which is incomplete at present and contains only nine elements. These are
89Ac, 104Rf, 105Ha, Unh (Unnihexium, Z = 106), 107Ns (Neilsobohrium), 108Hs (Hassium), 109Mt
(Meitherium), Uun (Ununnilium, Z = 110) and Uud (Unundium, Z = 112) or Ekamercury. The element,
Z = 111 has not been discovered so far. Thus, in all there are 39 d-block elements.

f-Block elements are called inner-transition elements. In these elements, the f-subshell of the
anti-penultimate is being progressively filled up. There are two series of f-block elements each
containing 14 elements. The fourteen elements from 58Ce – 71Lu in which 4 f-subshell is being
progressively filled up are called lanthanides or rare elements. Similarly, the fourteen elements from
90Th – 103Lr in which 5 f-subshell is being progressively filled up are called actinides.

Illustrations: Groups and periods

1. Which of the following is the period number of the element whose atomic number is 98
(1) 4 (2) 7 (3) 5 (4) 6
Ans. 2
Sol. The electronic configuration of the element with atomic number 98 is as follows.
1s2 , 2s2 , 2p6, 3s2, 3p6, 4s2 , 3d10, 4p6, 5s2, 4d10 , 5p6, 6s2, 4f14, 5d10, 6p6, 7s2, 5f 10
The last electron enters in f orbital, so it belongs to f block in the period.

2. The nuclei of elements X, Y and Z have same number of protons, but different numbers of neutrons.
According to Mendleev's periodic table, the elements X,Y and Z
(1) belong to same group and same period
(2) belong to different groups and different periods
(3) belong to same group and different periods
(4) are isotopes, which do not have different positions
Ans. 4
Sol. Isotopes have same number of protons (i.e. same atomic number). So they occupy same position
in the periodic table. However, due to different numbers of neutrons their atomic weights are different.

Exercise:
1. Which of the following has the same number of electrons in its outermost shell and penultimate shell ?
(1) Al3+ (2) Ca2+ (3) F– (4) N3–
Ans. 2

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 PERIODIC PROPERTIES

2. Which of the following statement is not correct about the electronic configuration of chromium atom ?
(Cr with atomic number = 24)?
(1) It has five electrons in 3d - sub - shell
(2) It has one electron in 4s-orbital
(3) The principal quantum numbers of its valence electrons are 3 and 4.
(4) It has six electrons in 3d-sub-shell
Ans. 4

TEMPORARY NOMENCLATURE
The IUPAC proposed a system for naming elements with Z > 100.
1. The names are derived by using roots for the three digits in the atomic number of the elements and
adding the ending -ium. The roots for the numbers are:
0 1 2 3 4 5 6 7 8 9
nil un bi tri quad pent hex sept oct enn
2. In certain cases the names are shortened; for example, bi ium and tri ium are shortened to bium and
trium, and enn nil is shortened to ennil.
3. The symbol for the element is made up from the first letters from the roots which make up the name. The
strange mixture of Latin and Greek roots have been chosen to ensure that the symbols are all different.

Illustration: Temporary nomenclature

According to the IUPAC system of naming elements, the symbol of the element of atomic number 121
will be
(1) Unu (2) Ubn (3) Ubu (4) Bus
Ans. 3

Exercise
The IUPAC name of the element with atomic number Z = 109 is
(1) U np (2) U ns (3) U no (4) U ne
Ans. 4

Anomalous behaviour of the first element of a group:

The first element of a group differs considerably from its congeners (i.e. the rest of the elements of
its group). This is due to (i) small size (ii) high electronegativity and (iii) non availability of d-orbitals
for bonding. Anomalous behaviour is observed among the second row elements (i.e., Li to F).

EFFECTIVE NUCLEAR CHARGE

 In a polyelectronic atom, the internal electrons repel the electrons of the outermost orbit. This results in
decrease the nuclear attraction on the electrons of the outermost orbit.
 Therefore, only a part of the nuclear charge is effective on the electrons of the outermost orbit. Thus, the
inner electrons protect or shield the nucleus and thereby decrease the effect of nuclear charge towards
the electrons of the outermost orbit.
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 Thus the part of the nuclear charge works against outer electrons, is known as effective nuclear
charge
Z *Z 
Z* = effective nuclear charge
 = shielding constant and Z = nuclear charge
Ascientist named Slater, determined the value of shielding constant and put forward some rules as
following.
(1) The shielding effect or screening effect of each electron of 1s orbital is 0.30.
(2) The shielding effect of each electrons of ns and np i.e. electron of the outermost orbit, is 0.35.
(3) The shielding effect of each electron of s or p orbitals of the penultimate orbit (n – 1) is 0.85.
(4) The shielding effect of each electron of s or p orbital of the prepenultimate orbit (n – 2) and below this is1.0.
Illustration: Screening or shielding
The screening effect of inner electrons of the nucleus causes
(1) Decrease in the ionisation energy
(2) Increase in the ionisation energy
(3) No effect on the ionisation energy
(4) Increases in the attraction of the nucleus to the electrons
Ans. 1
Sol. The attraction of the nucleus with the electron decreases so it becomes easy to extract the electron.

Exercise
1. The screening effect of d - electrons is -
(1) equal to the p - electrons (2) much more than p - electrons
(3) same as f - electrons (4) less than p - electrons
Ans. 4
2. The increasing order of effective nuclear charge in Na,Al, Mg and Si atoms
(1) Na < Mg < Si < Al (2) Na < Mg < Al < Si
(3) Mg < Na < Al < Si (4) Na = Mg = Al = Si
Ans. 2

Periodic Properties: Properties which are directly or indirectly related to the electronic configuration of
elements and show a regular gradation when we move from left to right in a period or from top to bottom
in a group are called periodic properties. Some important periodic properties are atomic size, ionization
energy electron affinity, electronegativity, valency, density, atomic volume, melting and boiling points etc.

(a) Atomic size

It refers to the distance between the centre of the nucleus of the atom to the outermost shell
containing electrons. Since absolute value of the atomic size cannot be determined, it is usually
expressed in terms of the following operational definitions.

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X X

A B

1/2 AB = rcovalent
(of element X)

X H H X X
H
E F
G H

1/2 EF = rvan der Waals of hydrogen in HX molecule

1/2 GH = rvan der Waals of X in HX molecule

n 2a 0
rn 
Z*
(i) Covalent radius. It is defined as one-half of the distance between the nuclei of two covalently
bonded atoms of the same element in a molecule.
Single Bond Covalent Radius, SBCR - (a) For Homoatomic molecules
dA–A = rA + rA or 2rA
dA  A
rA =
2
 (b) For hetrodiatomic molecules while electronegativity is approx same.
dA–B = rA + rB
 For hetronuclear diatomic moleculeA–B, while difference between the electronegativityvalues of
atomAand atom B is relatively larger, (XA and XB are the electron negativity in Pauling Scale).
dA–B = rA + rB – 0.09 |(XA –XB)| [Bond length or radius expressed in Å]
where XA and XB are electronegativityvalue of higher electronegative elementAand less electronegative
element B, respectively. This formula was given by Stevenson & Schomaker.
Note : Covalent radius is slightly smaller then actual radius.
(ii) Van der Waals’ radius. It is defined as one-half of the distance between the nuclei of two
non-bonded isolated atoms or two adjacent atoms belonging to two neigbhouring molecules
of an element in the solid state.
By definition, van der Waals’ radius of an element is always larger than its covalent radius.
Variation of atomic radii :
(i) Across the period atomic radii decreases
(ii) Where we move from 17th group to 18th atomic radii increases.

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Illustration: Atomic size

1. Calculate the bond length of C–X bond, if C–C bond length is 1.54 Å, X–X bond length is 1.00 Å and
electronegativity values of C and X are 2.0 and 3.0 respectively
Sol. (1) C–C bond length = 1.54 Å
1.54
rC = = 0.77 Å
2

1.00
rX = = 0.50 Å
2
(2) C–X bond length
dC–X = rC + rX – 0.09 |XX – XC|
= 0.77 + 0.50 – 0.09 |3–2| = 0.77 + 0.50 – 0.09 × 1 = 1.27 – 0.09 = 1.18 Å
Thus C–X bond length is 1.18 Å
2. Which of the following should be the longest bond ?
(1) S–H (2) O–H (3) N–H (4) P–H
Ans. 4
Sol. The atomic radius of P is largest out of O, S, N and P. Therefore. P–H bond will be the longest one.
Exercise
1. The atomic radii of O, N, Cl, F increase in the order
(1) F, O, N, Cl (2) N, O, F, Cl (3) F, O, N, Cl (4) F, Cl, O, N
Ans. 3
2. Whenever a list of radii is given, we find that the size of the noble gases is larger than the size of their
adjacent halogens. The reason is
(1) Noble gases have a complete octet
(2) They have a higher inter electronic repulsion
(3) In halogens it is covalent radii and in noble gases it is vanderwaals radii
(4) Noble gases cannot be liquified
Ans. 3

Variation in Period :
Li Be B C N O F Ne
Z 3 4 5 6 7 8 9 10
Z * 1.30 1.95 2.60 3.25 3.90 4.55 5.20 5.85
n 2 2 2 2 2 2 2 2
rn(pm) 123 90 80 77 75 74 72 160
(covalent) (Van der Waals)
Ionic size. An atom can be changed to a cation by loss of electrons and to an anion by gain of
electrons. A cation is always smaller than the parent atom because during its formation
effective nuclear charge increases and sometimes a shell may also decrease.On the other hand, the
size of an anion is always larger than the parent atom because during its formation effective nuclear
charge decreases e.g..
Mg2+ < Mg, Cl– > Cl
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1
Size of cation 
Amount of positive ch arg e or Z eff

Examples : (1) Mn > Mn+2 > Mn+3 > Mn+4 > Mn+6 > Mn+7 (size)
(2) Pb+2 > Pb+4
Size of anion  Amount of negative charge
O0 < O–1 < O–2

Size of Isoelectronic Series

Isoelectronic ions or species are the neutral atoms, cations or anions of different elements which have
the same number of electrons but different nuclear charge e.g..

The size of the isoelectronic species depends upon their nuclear charge. Greater the nuclear charge,
lesser the radii.

The ionic radii decrease moving from left to right across any period in the periodic table
Na+ Mg2+ Al3+
102 pm 72 pm 53.5 pm

1
Size in an isoelectronic series 
Nuclear charge
No. of protons 
Illustrations
What should be the order of size of H–1 , H+1 and H ?
H–1 H+1 H
1p 1p 1p
2e 0e 1e
+1
Sol. H < H < H –1

Exercise
1. Which of the following has the largest size
(1) N–3 (2) O–2 (3) K+1 (4) Ca+2
Ans. 1

2. Which one of the following is correct order of the size of iodine species?
(1) I > I– > I+ (2) I > I+ > I– (3) I+ > I– > I (4) I– > I > I+
Ans. 4

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IONISATION POTENTIAL
 The energy required to remove the most loosely bound electron from the outermost orbit of one mole of
isolated gaseous atoms of an element, is called ionisation potential (IP). This ionisation is an endergonic
or energy-absorbing process.
 An electron cannot be removed directly from an atom in solid state. For this purpose, the solid state is
converted to gaseous state and the energy required for this is called sublimation energy.
A I
IP
 A+1 II
IP III IP
 A+2  A+3
 The energy required to remove one electron from a neutral gaseous atom to convert it to monopositive
cation, is called first ionisation potential (I IP). The energy required to convert a monopositive cation to
a diapositive cation is called second ionisation potential (II IP) of an atom
 I IP < II IP < III IP because as the electrons go out of the atom, the ionic size goes on decreasing
and the amount of positive charge goes on increasing.
Factors Affecting Ionisation Potential
(i) Atomic size : When the size of an atom is very large the electron of the outermost orbit bound
to the nucleus by weaker attractive forces. Such an electron will be readily removed from the
atom. Therefore, the value of ionisation potential will be low.
1
Ionisation potential 
atomic size

(ii) Effective Nuclear Charge : Atomic size decreases with increase in effective nuclear charge
because, higher the effective nuclear charge stronger will be the attraction of the nucleus towards
the electron of the outermost orbit and higher will be the ionisation potential
Ionisation potential  Effective nuclear charge

(iii) Shielding Effect : The electrons of internal orbits repel the electrons of the outermost orbit due
to which the attraction of the nucleus towards the electron of the outermost orbit decreases and
thus atomic size increases and the value of ionisation potential decreases.
1
Ionisation potential 
shielding effect

(iv) Stability of half filled and fully filled orbitals : The atoms whose orbitals are half-filled (p3,
d5, f7) or fully-filled (s2 , p6 , d10 , f14) have greater stability than the others. Therefore, they
require greater energyto for removing out electron. However stability of fullyfilled orbitals is
greater than that of the half filled orbitals
I.P.of fully  filled orbitals  I.P. of half  filled orbitals

(v) Penetration power : In any atom the s orbital is nearer to the nucleus in comparison to p, d and
f orbitals. Therefor, greater energy is required to remove out electron from s orbital than from p,
d and f orbitals. Thus the decreasing order of ionisation potential of s, p, d and f orbitals is as
follows s > p > d > f
Io n isa tio n p o te n tia l  p e n e tra tio n p o w e r

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Periodic Table & Ionisation Potential

(a) In a Period :- The value of Ionisation potential normallyincrease on going from left to right in a
period, because effective nuclear charge increases and atomic size decreases.
Exceptions:
 In second period ionisation potential of Be is greater than that of B, and in the third period ionisation
potential of Mg is greater than that ofAl due to high stability of fully filled orbitals.
 In second period ionisation potential of N is greater than O and in the third period ionisation potential of
P is greater than that of S, due to stability of half filled orbitals.
 The increasing order of the values of ionisation potential of the second period elements is
Li < B < Be < C < O < N < F < Ne
The increasing order of the values of ionisation potential of the third period elements is
Na < Al < Mg < Si < S < P < Cl < Ar

Inner Transition Elements

The size of inner transition elements is greater than that of d block elements. Therefore the value of
ionisation potential of f block elements is smaller than that of d block elements and due to almost constant
atomic size of f block elements in a period the value of their ionisation potential remains more constant
than that of d block elements.
In a Group
 The value of ionisation potential normally decreases on going from top to bottom in a group because
both atomic size and shielding effect increase.
Exception :
 The value of ionisation potential remains almost constant from Al to Ga in the IIIAgroup.
(B>Al , Ga > In)
 IP1(Sn) < IP1(Pb)
 IP1(In) < IP1(Tl)
 In the periodic table the elements having highest value of ionisation potential is He.
 The values of ionisation potential of noble gases are extremely high, because the orbitals of outermost
orbit are fully-filled (ns2 , np6) and provide great stability.
 In a period, the element having least value of ionisation potential is an alkali metal (group IA) and that
having highest value is inert gas (Group 0)

Applications of Ionisation Potential

 The elements having high values of ionisation potential have low reactivity, e.g. inert gases.
 The value of ionisation potential decreases more on going from top to bottom in a group in comparison
to a period. Therefore, reactivity of metal increases and the atom forms a cation by loss of electrons.
1
Ionisation potential 
Re activity of metal

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 PERIODIC PROPERTIES

 The elements having low value of ionisation potential readily lose electron and thus behave as strong
reducing agents.
1
Ionisation potential 
Re ducing property
 The elements having low value of ionization potential readilylose electron and thus exhibit greater
metallic property.
1
Ionisation potential 
Metallic property

 The elements having low value of ionisation potential readily lose electron and thus have basic property.
1
Ionisation potential  Basic property

Illustration
1. Which of the following should be the order of increasing values of second ionisation potential of C6, N7,
O8 and F9
(1) C > N > F > O (2) C < F < N < O (3) C < F < N < O (4) C < N < F< O
Ans. 4
Sol. The second ionisation potential means removal of electron from a cation
C+1 (5e) = 1s2 , 2s2 , 2p1
N+1 (6e) = 1s2, 2s2, 2p2
O+1 (7e) = 1s2, 2s2, 2p3
F+1 (8e) = 1s2, 2s2 , 2p4
Therefore C < N < F < O
2. Which of the following should be correct for Z1 and Z2 in the following two processes
M+ + Z1  M+2 + e–
M+2 + Z2  M+3 + e–
1 1
(1) Z = Z2 (2) Z1 = Z2 (3) Z1 = Z (4) Z1 < Z2
2 1 2 2
Ans. 4
Sol. Z1 = second ionisation potential and Z2 = Third ionisation potential.
Second ionisation potential is always less than the third ionisation potential.
Exercise
1. One mole of magnesium in the vapour state absorbed 1200 kJ of energy. If the first and second ionization
enthalpies of magnesium are 750 and 1450 kJ mol–1 respectively, the final composition of the mixture is
(1) 69% Mg+, 31% Mg2+ (2) 59% Mg+, 41% Mg2+
(3) 49% Mg+, 51% Mg2+ (4) 29% Mg+, 71% Mg2+
Ans. 1

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 PERIODIC PROPERTIES

2. The incorrect statement in the following is

(1) The third ionisation potential of Mg is greater than the third ionisation potential ofAl
(2) The first ionisation potential of Na is less than first I.P of Mg
(3) The first I.P. of Al is less than the first I.P. of Mg
(4) The second I.P. of Mg is greater than the second I.P. of Na
Ans. 4

ELECTRON AFFINITY (EA)

 The energy released on adding up one mole of electrons to one mole of neutral atom (A) in its gaseous
state to form an anion (A–) is called electron affinity of that atom. In general, electron affinity is
associated with an exothermic process.
A(g) + e–  A– (g) , Heg = –En
 When one electron adds up to a neutral atom, it gets converted to a unit negative ion and energy is
released. On adding one more electron to the mononegative anion, there is a repulsion between the
negatively charged electron and anion. In order to counteract the repulsive forces, energy has to be
provided to the system. Therefore, the value of the second electron affinity is positive.
A– (g) + e–  A–2 (g) ,Heg = + En Heg : Electron gain enthalpy

Factors Affecting Electron Affinity

 Effective Nuclear charge
When effective nuclear charge is more, then the atomic size less. Hence EA increases.
Electron affinity  Effective nuclear charge

 Atomic Size orAtomic Radius

When the size or radius of an atom increases, the electron entering the outermost orbit is more weakly
attracted by the nucleus and the value of electron affinity is lower.

1
Electron affinity 
Atomic size

 Shielding Effect
Shielding effect is directlyproportional to atomic size and atomic size is inverselyproportional to electron
affinity.

1
Electron affinity 
Shielding effect

 Stability of Fully-Filled and Half-Filled Orbitals

The stability of the configuration having fully-filled orbitals (p6, d10, f14) and half-filled orbitals
(p3 , d5 , f7) is relatively higher than that of other configurations.

Periodic Table and Electron Affinity

In a period, atomic size decreases with increase in effective nuclear charge and hence increase in
electron affinity.
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 PERIODIC PROPERTIES

Exception :
 On going from C6 to N7 in the second period, the values of electron affinity decreases in stead of
increasing. This is because there are half-filled (2p3) orbitals in the outermost orbit of N, which are more
stable. On the other hand, the outermost orbit in C has 2p2 configuration.

 In the third period, the value of electron affinity of Si is greater than that of P. This is because electronic
configuration of the outermost orbit in P atom is 3p3 , which being half-filled, is relatively more stable

 The values of electron affinity of inert gases are zero, because there outermost orbit has fully-filled p
orbitals.

 In a period, the value of electron affinity goes on decreases on going from group IA to group IIA. The
value of electron affinity of the elements of group IIA is zero because ns orbitals are fully-filled and such
orbitals have no tendency to accept electrons.

In a Group
 The values of electron affinity normally decrease on going from top to bottom in a group because the
atomic size increases which decreases the actual force of attraction by the nucleus.

Exceptions (E.A. 2nd period p-block element < E.A. 3rd period p-block element)
 The value of electron affinity of F is lower than that of Cl, because the size of F is verysmall and compact
and the charge densityis high on the surface. Therefore, the incoming electron experiences more repulsion
in comparison to Cl . That is why the value of electron affinity of Cl is highest in the periodic table.

 The values of electron affinity of alkali metals and alkaline earth metals can be regarded as zero, because
they do not have tendency to form anions by accepting electron.

Illustrations
1. O(g) + 2e–1  O–2 (g) –E = + 744.7
The reason for the positive value of E is
(1) endothermic reaction (2) exothermic reaction
(3) both 1 and 2 (4) All of the above are wrong
Ans. 1
Sol. When electron is brought near O–1 there will be repulsion between them, and therefore the energy
will be positive i.e there will be absorption of energy during the process.

2. The increasing order of electron affinity values of O,S and Se is

(1) O < S < Se (2) S < O < Se (3) O < S > Se (4) Se < O > S
Ans. 3
Sol. Atomic size of Se is very large.

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 PERIODIC PROPERTIES

Exercise
1. The least electron affinityis found in
(1) Kr (2) O (3) N (4) B
Ans. 1
2. Of the following element of which electronic configuration will have the highest electron affinity
(1) 1s2 2s2 2p3 (2) 1s2 2s2 2p5 (3) 1s2 2s2 2p6 3s2 3p5 (4) 1s2 2s2 2p6 3s2 3p3
Ans. 3
ELECTRONEGATIVITY
 The measure of the capacity or tendency of an atom to attract the shared pair of electrons of the covalent
bond towards itself is called electronegativity of that atom.
 Electronegativity is a relative value that indicates the tendency of an atom to attract shared electrons
more than the other atom bonded to it. Therefore it does not have any unit. Pauling was the first scientist
to put forward the concept of electronegativity.
 The numerical value of electronegativity of an atom depends on its ionisation potential and electron
affinityvalues.
Factors Affecting Electronegativity
 Atomic size – Electronegativity of a bonded atom decreases with increase in its size.
1
Electronegativity 
Atomic size
 When effective nuclear charge is high the nucleus will attract the shared electrons with greater strength
and the electronegativitywill be high.
Electronegativity  Effective nuclear charge

 Shielding Effect – This effect increases the atomic size which decreases the electronegativity value.
1
Electronegativity 
Shielding effect

 Hybridisation state of atom – Electronegativity increases with increases in the s character of the
hybrid orbital. This is because the s orbital is nearer to the nucleus and thus suffers greater attraction
resulting in increase in electronegativity.
Electronegativity  Percentage of s character of the hybrid orbital

OR
1
Electronegativity 
Percentage of p character
of the hybrid orbital
 The number of covalent bonds present between two bonded atoms is known as bond order. With
increase in the bond order, the bond distance decreases, effective nuclear charge increases and thus
electronegativityincreases.
Bond order  Electronegativity
The increasing order of electronegativity is as follows : C–C < C = C < C  C
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 PERIODIC PROPERTIES

 Oxidation number – The electronegativity value increases with increase in oxidation number because
radius decreases with increase in oxidation number.
Oxidation number  Electronegativity

The increasing order of electronegativity is as follows : Fe < Fe+2 < Fe+3

 Electronegativity does not depend on stabilityof fully-filled or half-filled orbitals because it is simply the
capacity of nucleus to attact electrons. Here the electron does not enter the orbit of the atom.

Periodic Table and Electronegativity

Atomic size decreases on going from left to right in a period thus electronegativityincreases.Atomic size
increases on going from top to bottom in a group thus electronegativity decreases.
 Inert Gases – The electronegativity value of inert gases is zero, because they do not form covalent
bonds

 In a period, the electronegativityvalue of halogen is maximum, while the electronegativityvalue of alkali

metalis minimum.

 F has maximum electronegativityvalue in the periodic table, while Cs has minimum electronegativity.

 According to Pauling scale, the electronegativity value of F is 4.0, O is 3.5 N is 3.0 and Cl is 3.1.

Exceptions
 The elements of group II B i.e. Zn, Cd and Hg show increase in electronegativityvalue on going from top
to bottom in the group.
 The elements of group IIIA, i.e.Al to Ga show increase in electronegativity value on going from top to
bottom in the group.
 The elements of group IVA, show no change in electronegativity value on going from top to bottom in
the group from Si on words.

MEASUREMENT OF ELECTRONEGATIVITY
Pauling Scale
If two atoms,Aand B, having different electronegativityvalues, get bonded to form a molecule,AB, then
the bond between Aand B in A– B will have both covalent and ionic properties.
A–B = Observed bond energy – Energy of 100% covalent bond or A–B = D – EA–B
where D = Observed bond energy
EA–B = Bond energy of pure covalent bond of A – B.
The value of EA–A and EB–B is EA–B = 1/2 [EA–A + EB–B]
= 0.208 A–B = XA – XB where XA > XB or 0.043 × A–B = (XA – XB)2

XA – XB = 0.208 E AB  E A A  E BB in Kcal/mole

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 PERIODIC PROPERTIES

Mulliken Scale
Mulliken suggested that the value of electronegativity of an element as an average of the values of
ionisation potential and electron affinity of the element.
I.P.  E.A
XM = (in eV)
2
where XM = Electronegativity value as given by Mulliken
XM I.P.  E.A
Xp = =
2 .8 5.6

where Xp = Electronegativity value as given by pauling or Xp = 0.336 (XM – 0.615)

Allred-Roschov’s Scale

Z eff .e 2 Zeff
XAR = Xp = 0.359  0.744
r 2
r2
Zeff = Z –  where Z = Nuclear charge
 = Shielding constant
or Xp = 0.359 XAR + 0.744

Senderson’s Scale
In Senderson scale the stability ratio of an atom itself has been regarded as its electronegativity.
Average electron density of an atom
XS or S.R. =
Electron density of the isoelectronic inert gas
This is related to Pauling scale as follows
0.2
XP   0.77
S.R.  or Xs 

Illustration
Decreasing order of electronegativities of F, Cl, Br and I is
(1) F < Cl < Br < I (2) I < Br < Cl < F (3) Br < I > Cl >F (4) I < Br > Cl < F
Ans. 2
Sol. Electronegativity decreases in a group on going from top to bottom. Therefore I < Br < Cl < F

Exercise
1. Electronegativityof which of the following is high ?
(1) –CH3 (sp3) (2) H2C = CH2 (sp2) (3) CHCH (sp) (4) Equal in all
Ans. 3

2. Which of the following is the most polar bond

(1) N–H (2) Cl–H (3) O–H (4) Br–H
Ans. 3

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APPLICATIONS OF ELECTRONEGATIVITY
(i) Nomenclature
Compounds formed from two nonmetals are called binary compounds. Name of more electronegative
element is written at the end and "ide" is suffixed to it. The name of less electronegative element is
written before the name of more electronegative element of the formula.
Exercise
Write the correct formula and name of the following
(a) ICI or CII (b) FCl or ClF (c) BrCl or ClBr (d) BrI or IBr
(e) OF2 or F2O (f) Cl2O or OCl2
Sol. Correct formula Name
+
(a) I Cl – Iodine chloride
(b) Cl+ F– Chlorine fluoride
+
(c) Br Cl – Bromine chloride
(d) IBr Iodine bromide
(e) OF2 Oxygen difluoride
(f) Cl2O Dichlorine oxide
(ii) Nature of Bond
If difference of electronegativities of the two elements is 1.7 or more, then ionic bond is formed between
them whereas if it is less than 1.7, then covalent bond is formed. (HF is exception in which bond is
covalent although difference of electronegativity is 1.9)

(iii) Metallic and Nonmetallic Nature

Generally values of electronegativity of metallic elements are low, whereas electronegativity values of
nonmetals are high.
Partial Ionic Character in Covalent bonds
Partial ionic characters are generated in covalent compounds by the difference of electronegativities.

Hanny and Smith calculated percentage of ionic character from the difference of electronegativity.
Percentage of ionic character = 16(XA – XB) + 3.5(XA – XB)2
= 16 + 3.52
= (0.16 + 0.0352) × 100
(Here XA > XB)
XA is electronegativityof elementA
XB is electronegativityof element B
 = XA – XB
Calculation of Heat of Formation
Heat of formation = (XA – XB)2 × 100 Kcal/Mole
Bond Length
When difference of electronegativities of atoms present in a molecule is increases, then bond length
decreases. Shoemaker and Stephensen determined.
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 PERIODIC PROPERTIES

Bond length dA–B = rA + rB – 0.09 (XA – XB)

1
or dA–B = (DA–A + DB–B) – 0.09 (XA – XB)
2
Here XA > XB
Bond Energy
Bond energy is inversely proportional to bond length

Bond Strength & Stability

Bond strength and stability ofA–B increases on increases in difference of electronegativities of atomsA
and B bonded A–B.
Therefore H–F > H–Cl > H–Br > H–I

Reactivity
Bond energy is proportional to stability and stability is inversely proportional to reactivity.
H–F < H –Cl < H –Br < H–I

NATURE OF OXIDES
If difference of the two electronegativities (XO–XA) is 2.3 or more then oxide will be basic in nature.
Similarly if value of XO–XA is lower than 2.3 then the compound will be first amphoteric then acidic in
nature.
Oxide Na2 O MgO Al2O3 SiO2 P2 O5 SO3 Cl2O7
(XO–XA) 2.6 2.3 2.1 1.8 1.5 1.1 0.5
Nature Strong Basic Amphoteric weak Acidic Strong Strongest
basic acidic acidic acidic
Basic character of oxides  Difference of electronegativities of metal and oxide
Therefore basic character decreases in the period and acidic character increases.

NATURE OF HYDROXIDES
According to Gallis if electronegativity ofAin a hydroxide (AOH) is more than 1.7 then it will be acidic
in nature whereas it will be basic in nature if electronegativity is less than 1.7
For example NaOH and ClOH
Electronegativity(XA) 0.9 3.00
Nature Basic Acidic
If the value is more than XO–XH , then that hydroxide will be basic otherwise it will be acidic.
Polarity of cov alent bond  Difference of electronegativities

Exception :-
Negative N is written first in NH3 because it became very common from the very beginning. There is no
scientific basis for that. Otherwise according to rule it should have been written as H3N in the form of
trihydrogen nitride.
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Acidic and Basic Nature of Hydroxides of Elements

Acidic and basic nature of hydroxide of an elementAOH depends on ionisation potential ofA. If ionisation
potential ofAis low then it will give its electron to oxygen easily thusAOH will be basic.
Basic Character
1
 Basic Character of elements  Effective nuclear charge

1
 Basic Character of elements  Ionisation potential of metal

1
 Basic Character of elements  Electronegativity of metal

1
 Basic Character of elements  Oxidation number of metal

 Basic Character of elements  Metallic property

1
 Basic character of elements  Size of atom which forms anion (nonmetal)

Acidic Character
1
 Acidic character of elements  Atomic size

 Acidic character of element  Effective nuclear charge

 Acidic character of elements  Electronegativity of metal
 Acidic character of elements  Oxidation number of metal
1
 Acidic character of elements  Metallic Character

 Acidic character of elements  size of atoms which forms anion

Nature of Oxides
 Oxides of general metals are basic in nature whereas oxides of nonmetals are acidic in nature.
 Basic nature of oxides  Metallic nature
 Basic nature of oxides  Electropositive nature
1
 Basic nature of oxides  number of electrons in the outermost shell

 Acidic nature of oxides  Nonmetallic nature

 Acidic nature of oxides  Electronegative nature
 Acidic nature of oxides  number of electrons in outermost shell

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NATURE OF OXY ACIDS

 Those inorganic acids in which X–OH group is present are called oxy acids. (Here X = a non metal) like
HOCl is an oxy acid.

In a Period :
 Moving from left to right in a period strength of oxy acids increases like
Order of strength of oxy acid of elements of second period
H3BO3 < H2CO3 < HNO3
 Order of strength of oxy acids of elements of third period
H2SiO3 < H2SO4 < HClO4

In a Group :
 Moving upwards to downward in a group, strength of oxy acids decreases Like - in VA – HNO3 >
H3PO4
When amount of oxygen increases in an oxy acid of an element (i.e. on increasing oxidation state of
element) strength of acid increases like
(a) H2SO3 < H2SO4 (b) HClO < HClO2 < HClO3 < HClO4
Stability of acids also increases in the same order

NATURE OF HYDRIDES
 Moving from left of right in a period, nature of hydrides of nonmetal elements becomes basic to acidic.
Like
In second period NH3 H2 O HF
Weak base Neutral Acidic
(Amphoteric)
In third period PH3 H2S HCl
Very weak acid Weak acid Strong acid
 Moving upwards to downwards in a group, acidic nature and reducing power of hydrides of nonmetal
elements both increases but stability decreases. Like
Acid strength and reducing strength HF < HCl < HBr < HI
stability HF > HCl > HBr > HI
Illustration
Which of the following is most acidic ?
(1) H2Te (2) H2O (3) H2S (4) H2Se
Ans. 1
Sol. Te is biggest in size which will give H+ quickly
Exercise
Increasing order of basic character of NO2 K2O and ZnO is
(1) NO2 < ZnO < K2O (2) K2O < ZnO < NO2
(3) ZnO < K2O < NO2 (4) ZnO < NO2 < K2O
Ans. 1

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DENSITY
 Density in solid state changes on change in atomic number of elements.
 Moving left to right in the period densities of solid and liquid elements first increases, it is maximum in the
middle and then decreases.
 Moving upwards to downwards in a group, density generally increases but there is irregularity in this
order.
 Density decreases instead of increasing on moving towards Na to K in IA group and moving from Mg to
Ca in IIA group. Because penultimate value of K and Ca increases, due to which density gets reduced.
 Os (22.6 gm/cc) is most dense in solid elements and in liquids Hg is most dense (13.6 gm/cc)

DIAGONAL RELATIONSHIP
 Some elements of second period Li, Be, B show dissimilarities with other elements of their respective
group but show similarities with elements of third period like Mg,.Al, Si situated diagonally to them. It
is called diagonal relationship.

 Similarities between properties of Li and Mg are as follows.

(a) Li and Mg both react directlywith nitrogen to form lithium nitride (Li3N) and magnesium nitride
(Mg3N2) whereas other alkali metals of IA group does not form nitride.
(b) Fluoride carbonate and phosphate of Li and Mg are insoluble in water whereas these compounds
of other alkali metals are soluble.
(c) Li and Mg both are hard metals, whereas other metals of IA group are soft.
(d) LiOH and Mg(OH)2 both are weak base, whereas hydroxides of other elements of IA group
are strong base.
(e) Metallic bond in Li and Mg both are strong compare to other alkali metals .
(f) Their melting and boiling points are high.
(g) By thermal disintegration of LiNO3 and Mg (NO3)2 Li2O and MgO is obtained respectively.
(h) Thermal stability of Li2CO3 and Mg CO3 is very less compare to other alkali metals and they
liberate CO2 gas easily.
 Similarly Be shows similarity toAl of IIIAgroup compared to other elements of IIAgroup which are as
follows.
(a) Both elements do not provide colour to Bunsen burner.
(b) They both are comparatively stable in air.
(c) Both are insoluble in NH3 therefore do not form blue coloured solution.
(d) There is no tendency of making peroxide and superoxide in them.
(e) Reducing power is very less due to low value of standard electrode potential in the form of
oxidation potential.
(f) Be andAl both forms halogen bridge halides.

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METALLIC CHARACTER
It is the tendency to lose electrons.
On moving from left to right in a period metallic character decreases but increases on moving top to
bottom in a group. e.g. Metallic character across the period, Na > Mg > Al
Metallic character down the group e.g. group - I Cs > Rb > K > Na > Li

NON-METALLIC CHARACTER
It is the tendency to accept elecron.
On moving from left to right in a period the non-metallic character increases due to increase in the
effective nuclear charge but decreases on moving top to bottom in a group as on increase in the
number of shell force of attraction decreases.

Exercise
1. In the periodic table, with the increase in atomic number the metallic nature of elements
(1) Decreases in a period and increases in group (2) Increases in a period and decreases in group
(3) Increase both in a period and the group (4) Decreases both in a period and the group
Ans. 1

2. The element of the 17th group of the periodic table is likely to be

(1) Moderately non-metallic (2) Moderately metallic
(3) Strongly non-metallic (4) Stronglymetallic
Ans. 3

REACTIVITY
In general, the reactivity of the element decreases from top to bottom in a group except IA and IIA.
In these groups it increases. While in the period on moving left to right no such decrease or increase
are observed.
In case of metals generally the reactivity increases with decrease in ionization energy, so on the moving
left to right in a period I.E., increases, then the reactivity of metal decreases. In case of non-metals
the reactivity is proportional to Electronegativity & electron affinity so it increases in a period from
left to right but decreases in a group from top to bottom.

OXIDATION STATE
Except the IA and IIA group elements all the other elements shows variable oxidation state. IA &
IIA group elements show +1 and +2 oxidation state respectively.

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VALENCY
IA & IIA group elements show +1 and +2 electron valency. While most of the other group element
show variable valency. The VIIA group elements show –1 electrovalency and one co-valency. The
variable co-valency of p-block elements from top to bottom down the group varies as
(i) Co-valent state change into electrovalent.
(ii) Stability of higher valent state decrease while that of lower valent state increases.

ACID-BASE BEHAVIOUR OF OXIDES AND HYDROXIDES

The oxide or hydroxide of an element may act either a base or an acid depending upon its ionization
energy. If the ionization energy is low, it acts as a base and if the ionization energy is high, it acts
as an acid. The ionization energies of alkali metals are lowest, therefore, their oxides and hydroxides
are the strongest bases. Further, since the ionization energies of alkali metals decrease down the
group, the basic character of their hydroxides increases in the same order:
CsOH > RbOH> KOH> NaOH> LiOH.

The ionization energies of halogens are quite high, therefore, their oxides are strongest acids.
Further, since the ionization energies decrease down the group, therefore, the acidic character of their
oxides and hydroxides decreases in the same order: HClO4 > HBrO4 > HlO4
As we move from left to right within a period, the ionization energies usually increase and hence their
oxides and hydroxides show a gradual variation from strongly basic through amphoteric to
strongly acidic character. For example,
Na2O MgO Al2O3 P4O10 SO2 Cl2O7
Strongly basic Basic Weakly acidic Weakly acidic Very strongly acidic
acidic

Hence, Cs2O > Rb2O > K2O > Na2O > Li2O Basic nature (Down the group)
Ba(OH)2 > Sr (OH)2 > Ca(OH)2 > Mg(OH)2 Basic nature of hydroxide.

ATOMIC VOLUME
Atomic volume may be defined as the volume occupied by one mole atoms of the element at its
melting point in solid state. It is obtained by dividing the gram atomic mass of the element by its
density.
Atomic volume decreases along the period, reaches a minimum in the middle and then starts increasing.
This is due to the different packing arrangement of atoms in different elements in the solid state. For
example, P4, S8 etc.
In moving down the group atomic volume goes on increasing gradually.

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 PERIODIC PROPERTIES

GRAPHS OF PERIODIC PROPERTIES

Alkali Metals

Alkaline Earth Metals

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Element of Group IIIA

ATOMIC RADIUS
Atomic radius in (Å)

Tl(1.55)


In(1.5)
Al(1.24)
 
Ga(1.24)

B(0.8)

Carbon Family

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Nitrogen Family (Pnicogens)

Chalcogens

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Halogens

3-d Series

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GENERAL TREND OF DIFFERENT PROPERTIES IN THE PERIOD AND GROUPS

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IMPORTANT FACTS OF REMEMBER

1. Lowest electronegativity : Cs
2. Highest electronegativity : F
3. Highest ionisation potential : He
4. Lowest ionisation potential : Cs
5. Lowest electron affinity : Noble gases
6. Highest electron affinity : Chlorine
7. Least electropositive element : F
8. Lowest m. pt. metal : Hg
9. Highest m. pt. and b. pt. metal : W (Tungsten)
10. Lowest m. pt. and b. pt. non metal : He
11. Notorious element : Hydrogen
12. Lightest element : Hydrogen
13. Smallest atomic size : H
14. Largest atomic size : Cs
15. Largest anionic size : I–
16. Smallest cation : H+
17. Most electropositive element : Cs
18. Element with electronegativity
next to Fluorine : Oxygen
19. Group containingmaximum no.
of gaseous elements in periodic table : Zero group
20. Total number of gaseous elements
in periodic table : 11 (H, N, O, F, Cl, He, Ne, Ar, Kr, Xe, Rn)
21. Total number of liquid elements in
periodic table : 6 (Ga, Br, Cs, Hg, Fr, Uub)
22. Smallest anion : F–
23. Liquid element of radioactive nature : Fr
24. Total number of radioactive elements in
periodic table : 25
25. Volatile d-block elements : Zn, Cd, Hg, Uub
26. Element containing no neutron : H
27. Most abundant element on earth : Oxygen
28. Rarest element on earth : At (astatine)
29. Most abundant metal on earth : Al
30. Element havingmaximum tendency
for catenation : Carbon

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31. Non metal having highest m. pt., b. pt. : Carbon (diamond)

32. Metals showing highest oxidation number : Os (+8)
33. Most electrovalent compound : CsF
34. Most stable carbonate : Cs2CO3
35. Strongest alkali : CsOH
36. Strongest basic oxide : Cs2O
37. Best electricity conductor among metals : Ag
38. Best electricity conductor among non metals : graphite
39. Most poisonous element : Pu (Plutonium)
40. Liquid non metals : Br
41. Element kept in water : Phosphorous
42. Elements kept in kerosene : IA group element (except Li)
43. Elements sublime on heating : I2
44. Noble metals : Au, Pt. etc.
45. Amphoteric metal : Be, Zn, Al, Sn, Pb
46. Amphoteric non metal : Si
47. Metalloids elements : B, Si, As, Te, At, Ge, Sb
48. Non metals having metallic lusture : Graphite, Iodine
49. Heaviest naturallyoccuring element : Uranium
50. Poorest conductor of electricity : Diamond
51. Hardest naturallyoccuring element : Diamond
52. Lightest solid metal : Li
53. Amphoteric oxides : BeO, Al2O3, ZnO, PbO, PbO2, SnO, SnO2,
Sb2O3, As2O3 etc.
54. Neutral oxides of non metals : NO, CO, H2O, N2O
55. Dry bleacher : H2 O 2
56. Dry ice : Solid CO2
57. First man made element : Tc43 (Technicium)
58. Smallest period : Ist (2 elements)
59. Largest period in periodic table : 6th (32 elements)
60. Largest group in periodic table : IIIB (32 elements)
61. Most abundant d-block metal : Fe
62. Most abundant s-block metal : Ca
63. Highest density (Metals) : Os, Ir
64. Highest density (Non Metals) : Boron
65. Most abundant gas in atmosphere : Nitrogen
66. Most abundant element in the universe : Hydrogen
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EXERCISE-1
[SINGLE CORRECT CHOICE TYPE]

PERIODIC TABLE
Q.1 If A, B and C are the three element of Dobereiner's Triad and atomic mass of A and B are 7 and 15
respectively then the atomic mass of C is
(A) 1 (B) 11 (C) 23 (D) 25

Q.2 According to the Lother Meyer's curve which of the following statement is incorrect.
(A) The element having similar properties will occupy the same position in the curve.
(B)Alkaline earth metals are at the peaks of the curve.
(C) Halogens are at ascending part of the curve.
(D) The atomic volume of the elements in a period initially decreases and then increases.

Q.3 For which set of elements “diagonal relationship” is not existing.

(A) B, Si (B) Li, Mg (C) B, Mg (D) Be,Al

Q.4 Which of the following element is not a 'p' block element.

(A) Bi (B) Ga (C) Sn (D) Cd

Q.5 Which of following is not correctly matched

(A) d-block element : electronic configuration is ns0–2 (n – 1)d1 – 10.
(B) p-block element : electronic configuration is ns1 – 2 np1 – 6
(C) s-block element : electronic configuration is ns1 – 2
(D) Ce : f-block’s first member.

Q.6 Which is not transition element.

(A) Cu (B) Ac (C) Zn (D) Pd

Q.7 Which of the following atomic numbers represent s, p and d-block respectively.
(A) 10, 41, 23 (B) 20, 82,46 (C) 4, 44, 19 (D) 32, 55, 16

Q.8 The “atomic volume” of an element is defined as

(A) the volume occupied by an atom
(B) the volume occupied by one gram of an atom
(C) the volume occupied by the one gram-atom of an element
(D) none of these

Q.9 Find the odd element from the given electronic configuration.
(A) 1s2 2s2 2p6 3s1 (B) 1s2 2s1
(C) 1s2 2s2 2p6 3s2 3p1 (D) 1s2 2s2 2p6 3s2 3p6 4s1

Q.10 The total number of element present in 4th period in the long form of periodic table.
(A) 18 (B) 2 (C) 8 (D) 32

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Q.11 An element having electronic configuration of [Ar] 3d3 4s2 belongs to

(A) s-block (B) p-block (C) d-block (D) f-block

Q.12 Which of the following element is/are of d-block element (for which the atomic numbers are given).
(A) 19 (B) 81 (C) 46 (D) 58

Q.13 The elements in which 5f-orbitals are progressively filled are called as
(A) Lanthanides (B)Actinides
(C) Transition elements (D) None of these

Q.14 Which of the following is ‘d’ block element.

(A) Bi (B) Sn (C) Nb (D) In

Q.15 The elements P, Q and R are one of the Dobereiner's triad of elements in the increasing order of their
atomic masses. If the atomic masses of P, Q and R are x, y and z respectively, then
(A) x = 2y + z (B) z = x + y (C) z = 2x – y (D) x + y + z = 3y

Q.16 Which of the following statement is incorrect for Lother Mayer's curve ?
(A)Atomic volumes of elements were taken on y-axis and atomic masses of elements on x-axis.
(B)All the peaks were occupied by alkali metals.
(C) Halogens were present on the descending curve.
(D)Alkaline earth metals were present on the descending curve.

Q.17 Which one of the following statements is not correct?

(A) Li shows similarity in properties with Mg
(B) Li, Na and K forms Doberenier's Triads.
(C) In the Lother Meyer's curve alkaline earth metals occupy the ascending positions of the curve
(D) IUPAC name of the element having atomic number 112 is Uub.

Q.18 The period number, group number, and block of the element having atomic number 39 will be :
(A) 5, 5, d (B) 5, 4, d (C) 5, 3, d (D) 5, 15, p

Q.19 In the Modern long form of periodic table, 4th period contains only 18 elements. It is due to filling of
electrons in the :
(A) 4s, 4p and 4d sub-shells (B) 4s, 3d and 4p sub-shells
(C) 4s, 4p, 4d and 4f sub-shells (D) 3s, 3p and 3d sub-shells

Q.20 Which of the following element does not belongs to p-block?

(A) Cl (B) S (C) H (D) Ne

Q.21 If x, y and z are the three elements of Dobereiner's triad and the atomic masses of x and z are 7 and 23
respectively, the atomic mass of y is
(A) 15 (B) 11 (C) 12 (D) 24

Q.22 In the general electronic configuration

(n – 2)f1–14 (n – 1)d0–1 ns2, if value of n = 7 the configuration will be :
(A) Lanthanides (B)Actinides (C) Transition elements (D) None

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Q.23 Find the species not having same number of d-electron in last possible filled d-subshell as in Zn.
(A) Ga (B) Pd (C) Cd (D) Pt

Q.24 According to modern periodic law, properties of the elements are the periodic functions of their
(A)Atomic weight (B) Surface area (C)Atomic number (D) Density

Q.25 The element having the lowest atomic number and a ground state electronic configuration of (n–1) d6 ns2
is placed in
(A) Fifth period (B) Fourth period (C) Sixth period (D) Third period

Q.26 Select the configuration of neutral atom(s), which belongs to s-block?

(A) [Xe] 4f14 5d10 6s2 (B) [Xe] 5d1 6s2
(C) [Xe] 4f7 3d0 6s2 (D) [Xe] 6s2

Q.27 Select the pair of elements which are present in same group but in different sub group in Mendeleev's
periodic table.
(A) F, Ar (B) Cl, B (C) K, Cu (D) Be, Mg

Q.28 Select the pair of elements which are present in same period in long form of periodic table.
(A) C, Ar (B) Sc, Y (C) Na, La (D) P, S

Q.29 If an orbital can have maximum 4 electrons then, how may elements can be present in 8th period?
(A) 100 (B) 75 (C) 128 (D) 64

Q.30 Principle of modern periodic table is given by :

(A) Mosley (B) Mendeleef (C) Doberinier (D) Newland

Q.31 In the Lother - Mayer graph, A,B,C,D & E element are

E
D
C
Atomic Volume

B
A

Atomic Weight

(A) Halogens (B)Alkaline earth metals

(C)Alkali metals (D) Transition metals

Q.32 Most of the 'd' block elments are known as :

(A)Alkali metals (B)Alkaline earth metals
(C) Innertransition element (D)Transition element

Q.33 If the atomic number of an element is 33, it will be placed in the periodic table in the ––––––
(A) first group (B) third group (C) fifth group (D) seventh group

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Q.34 Match column I (atomic number) with column II (position in the Periodic Table) and select the correct
answer using the codes given below:
Column I Column II
I. 52 P. s-block
II. 56 Q. p-block
III. 57 R. d-block
IV. 60 S. f-block
(A) I – P, II – Q, III – S, IV – R
(B) I – Q, II – P, III – S, IV – R
(C) I – P, II – Q, III – R, IV – S
(D) I – Q, II – P, III – R, IV – S

Q.35 In which group of periodic table, the elements of 4th, 5th and 6th period have different ground state
electronic configuration for last two shells, from each other?
(A) 8 (B) 9 (C) 10 (D) 18

Q.36 Identify the atom which has ground state configuration [Ar] 3d10 4s2 4p1
(A)Al (B) Ga (C) In (D) T

Q.37 Name of element with atomic number (z) = 110.

(A)Unnilbium (B)Ununnillium
(C)Unnilunium (D) Ununtrium

Q.38 Which of the following statement is correct for an element having atomic number (z) = 98?
(A) It is s-block element.
(B) It is p-block element.
(C) It is transition element.
(D) It is inner transition element.

Q.39 Which of the following is not a bridge element of in Mendeleev's table?

(A) Mg (B)Al (C) Si (D)Ar

Q.40 What will be the atomic number of yet undiscovered element directly below Fr in periodic table?
(A) 117 (B) 118 (C) 119 (D) 120

Q.41 Which of the following is d-block element.

(A) Bi (B) Sn (C) Nb (D) Pb

Q.42 The outer electronic configuration of an element in ground state is 5s2 4d10 5p3. The properties of
element is likely to be similar to that of
(A) Chlorine (B) Sulphur
(C) Phosphorus (D)Aluminium

Q.43 In the sixth period, the orbitals are filled as-

(A) 6s 5f 6d 6p (B) 6s 4f 5d 6p
(C) 5s 5p 5d 6p (D) 6s 6p 6d 6f

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Z=5

Q.44
X

In above figure if 'Z' is the atomic number then identify the period number of element 'X' in periodic
table-
(A) 5th (B) 4th (C) 6th (D) 7th

Q.45 Identify the group number of T element in periodic table.

(A) Group number = 13 (B) Group number = 4
(C) Group number = 16 (D) Group number = 7

Q.46 Mendleeve left the space for elements in periodic table, the element is not ______.
(A) Ga (B) Sc (C) Ge (D) Te

Q.47 The number of elements in 6th period of the modern periodic table are :
(A) 8 (B) 18 (C) 32 (D) None of these

Q.48 The number of groups in modern periodic table that belong to d-block are :
(A) 18 (B) 10 (C) 6 (D) 2

Q.49 Which of the following is a transition element?

(A) Zn (B) Cd (C) Hg (D) Cu

Q.50 The number of elements present in the group 3 of the modern periodic table is:
(A) 4 (B) 8 (C) 18 (D) 32

Q.51 The elements with given atomic numbers that belong to the group number 16 of the modern periodic
table is:
(A) 34, 52 (B) 15, 33 (C) 38, 56 (D) None of these

Q.52 In the modern periodic table the maximum number of elements are present in :
(A) Group I and period number 5 (B) Group III and period number 6
(C) Group V and period number 7 (D) Same for all

EFFECTIVE NUCLEAR CHARGE

Q.53 Choose the correct statement from the following :
(A) Zeff on ‘d’ electron of Sc2+ is 18
(B) Zeff values on an electron present in 4s and 4p orbital of an atom are identical.
(C) Zeff values on an electron present in 3s and 4s orbital of an atom are identical.
(D) the screening constant value on one electron in H– ion is 0.35.

Q.54 According to Slater rule, which set of elements show incorrect order of zeff.
(A) Al > Mg (B) Na > Li (C) K > Na (D) None of these

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Q.55 The value of screening constant () for N-atom is 3.10 and that for O-atom is
(A) 3.10 (B) 2.75 (C) 3.45 (D) 3.80

Q.56 In a given shell the order of screening effect is

(A) s > p > f > d (B) s > d > p > f (C) s > p > d > f (D) s < p < d < f

Q.57 Calculate the effective nuclear charge for the outer most electron of oxygen atom.
(A) 3.45 (B) 4.55 (C) 0.85 (D) 6.4

Q.58 What will be the difference of Zeff in N and O for last electron.
(A) 0.35 (B) 0.65 (C) 2.1 (D) 0.85

Q.59 The outermost and penultimate shell of an element contains 2 and 8 electrons, respectively.The effective
nuclear charge for the valence electron of this element, according to Slater's Rule, should be :
(A) 2.20 unit (B) 2.50 unit (C) 2.85 unit (D) 7.15 unit

Q.60 Which of the following pair of elements have the same value of shielding constant () for 3s-electron.
(A) Mn & Zn (B) Fe & Na (C) Ar & Cl (D)All of these

Q.61 Which of the following pair has the same value of screening constant for '3s' electron?
(A) Cl & Mg (B) Mg & Ca (C) N & Na (D) K & Ca

Q.62 The order of screening effect of electrons of s, p, d and f-orbitals of a given shell of an atom on its outer
shell electrons is :
(A) s > p > d > f (B) f > d > p > s (C) p < d < s < f (D) f > p > s > d

Q.63 Effective nuclear charge on last electron of Fe2+

(Using Slater's Rule)
(A) 7.5 (B) 7.45 (C) 6.25 (D) 19.75

Q.64 Zeff for the valence electron ofAl (Z = 13) is :

(A) 9.50 unit (B) 3.50 unit (C) 3.85 unit (D) 3.15 unit

Q.65 Find Zeff (using Slater's Rule) on 3d electron of Cu(29)

(A) 8.3 (B) 6.85 (C) 7.85 (D) None of these

Q.66 Choose the following atom which has maximum value of Zeff ?
(A) Na (B) Li (C) S (D) O

Q.67 Calculate the value of Zeff for 3d electron of 21Sc.

(A) 18.69 (B) 21.69 (C) 3.69 (D) 3.00

Q.68 The value of  for the 4s and 5s electron of Rb is respectively ?

(A) 27.75 and 34.80 (B) 28.95 and 34.80
(C) 27.75 and 28.10 (D) 28.10 and 28.95

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SIZE
Q.69 In Which of the following case the size ratio is minimum :
(A) Li– / Li (B) H– / H (C) Na– / Na (D) I– / F–

Q.70 Among the following species the highest radius is of

(A)Al3+ (B) F¯ (C) Na+ (D) N3–

Q.71 Select the correct sequence of increasing radius (left to right)

(A) Se2–, O2–, F¯ (B) Ca2+, Ar, K+ (C) Se, As, Ge (D) Fe, Fe2+, Fe3+

Q.72 Atomic radii of fluorine and neon inAngstrom units are respectively given by
(A) 0.72, 1.60 (B) 1.60,1.60 (C) 0.72, 0.72 (D) 1.60, 0.72

Q.73 Choose the correct ionic radius order:

(A) N3– < N2– (B) N3– < P3– (C) K+ < Ca2+ (D) O2– < Mg2+

Q.74 In which of the following compound size of cation to anion ratio is minimum :
(A) CsF (B) LiI (C) LiF (D) CsI

Q.75 The Lanthanide contraction is caused by

(A) sudden increase of number of proton inside the nucleus of an atom.
(B) sudden decrease of number of valence shell electrons.
(C) presence of large number of d and f-electrons having poor shielding effect.
(D) the repulsion of inner shell electrons.

Q.76 Atomic radius variation of an unknown group in the periodic table is as below
Atomic radius

• •
• •

A B C D E
The element B & C respectively are :
(A) Cl & Br (B) Be & Mg (C) Si & Ge (D) Al & Ga

Q.77 Choose the incorrect ionic radius order.

(A) Al3+ < Li+ (B) O2– > C4– (C) Cl¯ < S2– (D) Na+ > Li+ > H+

Q.78 The smallest size cation and anion available are respectively.
(A) H+ and H¯ (B) H+ and F¯ (C) Li+ and F¯ (D) Li+ and H¯

Q.79 Select the correct order of ionic radii.

(A) O2– > S2– > Se2– > Te2– (B) S2– > O2– > Se2– > Te2–
(C) Te2– > Se2– > S2– > O2– (D) Se2– > Te2– > O2– > S2–

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Q.80 Which of the following is smallest anion.

(A) F (B) H (C) Cl (D) O2–

Q.81 Which of the following is the correct increasing size?

(A) Cl¯< Ca2+ < S2– < Al3+ (B) Mg2+ < K+ < Li+ < Al3+
(C) Mg2+ < Na+ < F¯ < O2– < N3– (D) F¯ < Na+ < Mg2+ < O2–

Q.82 Which of the following elements have smaller size than carbon?
(A)Lithium (B) Nitrogen (C) Neon (D) Sodium

Q.83 For an element, the covalent radius is xÅ, metallic radius is yÅ and the Vanderwaal's radius is zÅ. Which
of the following order is correct?
(A) x < y < z (B) y < x < z (C) z < y < x (D) x < z < y

Q.84 Which of the following is incorrect order of ionic radii?

(A) N– < N2– < C4– (B) O– < N3– (C) Mg+ < Al3+ (D) Si4+ < Al2+ < Al+

Q.85 Choose the correct order of size.

(I) Fe2+ > Fe3+ (II) Cu < Zn (III) Cu2+ > Cu+ (IV) Hg22+ > Hg2+
(A) I, II & IV (B) I, II & III (C) I, III & IV (D) II & IV

Q.86 Among the following species the highest radius is of

(A) Na+ (B) Mg2+ (C) Al3+ (D) Si4+

Q.87 The correct order of atomic radii is

(A) K+ < Ca2+ < Cl– < S2– (B) Cl– < K+ < Ca2+ < S2–
(C) Cl– < S2– < K+ < Ca2+ (D) Ca2+ < K+ < Cl– < S2–

Q.88 The correct order of ionic radii is

(A) N3– > Na+ > O2– > F¯ (B) Na+ > O2– > N3– > F¯
(C) O2– > F¯ > Na+ > N3– (D) N3– > O2– > F¯ > Na+
Q.89 The correct order of ionic radii is :
(A) Te2– > I– > Cl– > Ar+ (B) I– > Te2– > Cl– > Ar+
(C) I– > Te2– > Ar+ > Cl– (D) I– > Cl– > Te2– > Ar+

Q.90 The Lanthanide contraction is responsible for the fact that :

(A) Zr and Y have almost the same radius.
(B) Zr and Nb have similar oxidation state.
(C) Zr and Hf have almost the same radius.
(D) Zr and Zn have the same oxidation state.

Q.91 Select the correct order of ionic radii :

(A) Te2– > Se2– > S2– > O2– (B) Te2– < Se2– < S2– < O2–
(C) Te2– = Se2– > S2– = O2– (D) None

Q.92 Which one is correct order of the size of the Nitrogen species?
(A) N+ < N < N– (B) N > N¯ > N+ (C) N+ > N¯ > N (D) N > N+ > N¯

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Q.93 Which one is correct order of the size of the iodine species?
(A) I¯ > I > I+ (B) I > I¯ > I+ (C) I+ > I¯ > I (D) I > I+ > I¯

Q.94 Correct order of radius among the following

F¯, Al3+, Na+ are
(A) Al = Na+ = F¯
3+ (B) Al3+ > Na+ > F¯
(C) Al3+ = Na+ > F¯ (D) Al3+ < Na+ < F¯

Q.95 The ionic radii of Fe2+ and Fe3+ are x and y respectively the correct relationship between x and y is :
(A) x > y (B) x < y (C) x = y (D) can’t be predicted

Q.96 The ions O2–, F¯, Na+, Mg2+ and Al3+ are isoelectronic. Their ionic radii show:
(A) an increase from O2– to F¯ and then decrease from Na+ to Al3+
(B) a decrease from O2– to F¯ and then increase from Na+ to Al3+
(C) a significant increase from O2– toAl3+
(D) a significant decrease from O2– to Al3+

Q.97 The correct order of ionic radii is :

(A) O– > F– > Li+ > B3+ (B) F– > O– > Li+ > B3+
(C) F– > B3+ > O– > Li+ (D) O– > F– > B3+> Li+

Q.98 Which of the following pair of species having nearly same atomic size
(A) Zr & Hf (B) Pd & Pt (C) Fe & Co (D)All of these

Q.99 Select the pair of almost same size.

(A)Al, Ga (B) Zr, Hf (C) Fe, Co (D)All of these

Q.100 Choose the correct order of atomic / ionic radii.

(A) Sc < Y < La (B) Fe < Co < Ni
2+ 2+
(C) Be < Mg < Al 3+ (D) Tl+ < Pb2+ < Bi3+

Q.101 Arrange in the increasing order of atomic radii of the following elements O, C, F, Cl, Br
(A) F < O < C < Cl < Br (B) F < C < O < Cl < Br
(C) F < Cl < Br < O < C (D) C < O < F < Cl < Br

Q.102 The ionic radius of Na+, Mg2+ and Al3+ ions are in order.
(A) Na+ < Mg2+ < Al3+ (B) Na+ > Mg2+ > Al3+
(C) Na+ = Mg2+ = Al3+ (D) Na+ < Al3+ < Mg2+

Q.103 In following compound which has minimum ionic radius of maganese is :

(A) Mn2(SO4)3 (B) MnO
(C) KMnO4 (D) MnO2

Q.104 Choose the compound in which 'Cr' atom has minimum atomic radii:
(A) Cr2O3 (B) CrO
(C) K2Cr2O7 (D)All molecule has same atomic radii of Cr

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Q.105 Which of the following pair of element has incorrect order of atomic radii?
 Co
(A) Fe ~ (B) La ~ Y (C) Pt ~ Pd  Hf
(D) Zr ~

Q.106 Atom which has largest atomic radii in following -

(A) Se (B) Br (C) Te (D) I

Q.107 Which options are correct for atomic radii ?

(A) Ne > F (B) F > Cl (C) F > Ne (D) Cl > Ar

Q.108 Which of the following has the largest size?

(A) K+ (B) Ca+2 (C) Ar (D) S2–

Q.109 Among the following species the highest radius is of

(A)Al3+ (B) Mg2+ (C) Li+ (D) Na+

IONISATION ENERGY
Q.110 Find the highest ratio of IP values of given pair of elements :
(A) He : Ne (B) Ne : Ar (C) He : Xe (D) Kr : Xe

Q.111 Which one of the following electronic configuration of an atom has the lowest ionisation energy
(A) 1s22s22p3 (B) 1s22s22p63s1 (C) 1s22s22p6 (D) 1s22s22p5

Q.112 The first five ionization energies of an element are 9.1, 16.2, 24.5, 35 and 205.7 eV respectively. Then
number of valence electron in the atom is
(A) 2 (B) 3 (C) 4 (D) 5

Q.113 Which one of the following electronic configuration of an atom has the highest ionisation energy
(A) 1s22s22p3 (B) 1s22s22p63s1 (C) 1s22s22p6 (D) 1s22s22p5

Q.114 Which of the following magnetic moment values will correspond to highest ionisation energy for cobalt
specie.
(A) 2 2 (B) 15 (C) 35 (D) 24

Q.115 Which of the following has 2nd I.P. < Ist I.P.
(A) Mg (B) Ne (C) C (D) None of these

Q.116 Highest difference between Ist & IInd ionisation energies will be observed in:
(A) Li (B) B (C) O (D) F

Q.117 Ionisation energies of element X are given below kJ/mol

IE1 IE2 IE3
520 7,340 11,000
If ‘X’ reacts with different elements which compounds are possible
(A) XF (B) X2O (C) X3N (D)All of above

Q.118 The correct order of ionisation energy of Al, K, Fe, Mg is

(A) K < Al < Mg < Fe (B) K < Mg < Al < Fe
(C) Mg < K < Al < Fe (D) Mg < Fe < Al < K
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Q.119 One element (A) is having four valence shell electron and which of following values will be maximum.
(A) EA of 'A' (B) IE4 – IE3 (C) IE5 – IE3 (D) IE2 – IE1

Q.120 The 2nd ionisation potential of Mg is less than that of Na because

(A) Atomic size of Mg is less than that of Na.
(B) Atomic size of Mg is greater than that of Na.
(C) 2nd electron removal from Na occur from inert gas configuration, while the same for Mg results inert
gas configuration.
(D) Both are having same Zeff value for 3s electron.

Q.121 Which of the following set of elements are having strongest tendencyto form cation?
(A) I, Cl, Br (B) C, Sn, Se (C) Na, K, Sr (D) Mn, Ti, Fe

Q.122 The ionisation potential values 54.40 eV & 39.30 eV correspond to

(A) H+ & H (B) Li & Li+ (C) He & He+ (D) He+ & He

Q.123 The ionisation energy for ‘Sc’ , ‘Y’and ‘La’are x, y and z Kcal/mol respectively. Choose the correct
relationship between them.
(A) z > x  y (B) x > y > z (C) x > z  y (D) x < y > z

Q.124 For an element ‘A’.: A IE 

1
A+ IE2  A2+ IE 
3
A3+  ...................
The IE1 and IE3 values are 27 kJ/mole and 51 kJ/mole respectively. Then the value of IE2 is ________
kJ/mole.
(A) 21 (B) 33 (C) 59 (D) 63

Q.125 Which of the following atom has highest ionisation energy.

(A) N (B) O (C) P (D) S

Q.126 Rb forms Rb+ ion but it does not form Rb2+ because
(A) Very low value of (I.E.)1 and (I.E.)2
(B) Very high value of (I.E.)1 and (I.E.)2
(C) low value of (I.E.)1 and low value of (I.E.)2
(D) low value of (I.E.)1 and high value of (I.E.)2

Q.127 Choose the correct Ionisation potential order :

(A) O¯ > O (B) N¯ > N (C) H¯ > H (D) None of these

Q.128 An+(g)  A ( n 1) (g) + e
X

In above process 'X' is

(A) Electron gain enthalpy (B) Electronegativity
(C) Ionisation energy (D) None of these

Q.129 H IE1 (First Ionisation Enthalpy) of Na, Mg and Si is 496, 737 and 786 KJ mol–1, respectively. What

will be the ΔH IE1 value ofAl?

(A) 760 KJ mol–1 (B) 450 KJ mol–1 (C) 580 KJ mol–1 (D) 800 KJ mol–1
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(Successive I.E.)

z
b
y
Q.130 H x H a

+1 +2 +3 +4 +1 +2 +3
(Charge on the ion) (Charge on the ion)
Graph - I Graph - II

Above graphs represent successive ionisation energies of an element.

Given : x < y < 11 eV and z > 16 eV ; a < 11 eV and b > 16 eV
Which of the following is incorrect according to above two graphs?
(A) Graph I may belong to the elements of 13th group.
(B) Graph II may belong to the elements of 2nd group.
(C) Stable oxidation state of metal ion according to Graph-II would be +2.
(D) ns2np1 may be the general electronic configuration of element according to Graph-II.

Q.131 Which of the following is the strongest reducing agent in aqueous solution?
(A) 1s2 2s2 2p6 3s2 3p6 4s1 (B) 1s2 2s1
2 2
(C) 1s 2s 2p 3s6 1 (D) [Xe] 6s1

Q.132 For an element 'A' belonging to alkaline earth metal family.

A  A+ IE 
 A2+ IE  A3+ IE
 
 A4+ ..... are defined. If IE3 and IE4 are respectively
IE1 2 3 4

4.9 and 6.5 M J/ mol. What will be the values of IE1 and IE2 respectively.
(A) 1, 4 (B) 0.6, 1.1 (C) 4, 4.5 (D) 1.5 , 5.2

Q.133 The ionisation enthalpyof sodium is 500 kJ/mol at TK. How many sodium atoms maybe converted into
sodium ions (Na+) by the absorption of 200 J heat at TK ? (NA = 6 × 1023)
(A) 2.4 × 1023 (B) 2.4 × 1020 (C) 1.5 × 1021 (D) 1.5 × 1024

Q.134 The successive ionisation energies of an element (in eV/atom) are :

The outer electronic configuration of the element may be :

(A) ns2 np0 (B) ns2np3 (C) ns2np1 (D) ns2np2

Q.135 Ionisation energies of Cl– , Cl and Cl+ are respectively (in KJ/mol)
(A) 1251, 349, 2300 (B) 2300, 349,1251
(C) 349, 1251, 2300 (D) 349, 2300, 1251

Q.136 Which of the following isoelectronic species has the lowest ionisation energy?
(A) S2– (B) K+ (C) Cl¯ (D) Ca2+
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Q.137 Which ionisation potential in the following equations involves the greatest amount of energy?
(A) K+  K2+ + e– (B) Ca+  Ca2+ + e– (C) Fe  Fe+ + e– (D) Li+  Li2+ + e–

Q.138 Which of the following has the lowest second ionisation energy?
(A) Sc (B) Ti (C) V (D) Ca

Q.139 Which of the following elements has the highest ionisation energy?
(A) [Ne] 3s23p1 (B) [Ne] 3s23p3 (C) [Ne] 3s23p2 (D) 3d10, 4s2 4p3

Q.140 The first ionisation potential (in eV) of N , O atoms are:

(A) 14.6, 13.6 (B) 13.6, 14.6 (C) 13.6, 13.6 (D) 14.6, 14.6

Q.141 Ionisation potential of which element is highest?

(A) H (B) Cl (C) He (D) Fr

Q.142 Which of the following elements has the lowest ionisation potential?
(A) Na (B) K (C) Mg (D)Al

Q.143 Inert pair effect is prominent character of

(A) p-block element (B) d-block element (C) s-block element (D) f-block element

Q.144 For element, A there is large energy difference between 5th and 6th ionisation energy. This element is
member of
(A) Pnictogen family (B) Chalcogen family (C) Halogen family (D) Noble gases

Q.145 Second ionization potential of Li, Be and B is in the order

(A) Li > Be > B (B) Li > B > Be (C) Li > Be < B (D) B > Be > Li

Q.146 Consider following electronic configuration of atoms and select correct code in order of increasing
ionization energy
[I] 1s2 2s2 2p6 3s2 [II] 1s2 2s2 2p6 3s1 [III] 1s2 2s2 2p4
[IV] 1s2 2s2 2p5 [V] 1s2 2s2 2p6
(A) [II] < [I] < [III] < [IV] < [V] (B) [II] < [III] < [IV] < [I] < [V]
(C) [II] < [IV] < [III] < [I] < [V] (D) [II] < [III] < [I] < [IV] < [V]

Q.147 The incorrect statement among the following is :

(A) The first ionisation energy of calcium is more than first ionisation energyof gallium
(B) The second ionisation energy of copper is greater than that of potassium
(C) The third ionisation energy of Mg is greater than the third ionisation energy ofAl
(D) The IE1 of Mg+ is less than the IE1 of Na+

Q.148 Choose the correct ionisation energy order.

(A) Li < B < Be < C < N < O < F
(B) Na < Mg < Al < Si < S < P < Cl
(C) K < Ga < Ca < Ge < As < Se < Br
(D) Rb < Sr < In < Sn < Sb < Te < I
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Q.149 Select correct graph, which is plotted between Ionisation Energy of 2nd period elements and their
atomic number.

IE IE
IE IE

(A) (B) (C) (D)

3 4 5 6 7 8 9 10
3 4 5 6 7 8 9 10 3 4 5 6 7 8 9 10 3 4 5 6 7 8 9 10
Atomic number
(Z) Atomic number (Z)

Q.150 Which of the following has the highest second ionisation energy?
(A) Cr (B) Mn (C) Co (D) Fe

Q.151 Ionisation energy order is :

(A) Li < Be > B (B) Be < B < C (C) C < N < O (D) N < O < F

Q.152 The incorrect order of IInd ionisation energy is

(A) Cu > Zn (B) Cr > Mn (C) Na > Mg (D) Mg > Al

Q.153 Select the correct order of IInd I.E. of C, N, O, F.

(A) C > N > O > F (B) C < N < O < F (C) C < N < O > F (D) C < N > O < F

Q.154 Successive ionization enthalpies (in eV/atom) of an element are 5, 8, 9, 90, 100. The number of
valence electrons are :
(A) 1 (B) 2 (C) 3 (D) 4

Q.155 Which of the following element will have highest ionization energy?
(A) H (B) He (C) Ne (D) F

Q.156 The correct order of second ionisation energy.

(A) N > O (B) Li > Ne (C) P > N (D) Br > Cl

Q.157 I and III ionisation energies of an element are 40 and 60 eV/atom respectively. II ionization energy can
be
(A) 51 eV/atom (B) 39 eV/atom (C) 65 eV/atom (D) 100 eV/atom

Q.158 Which of the following is incorrect statement(s):

(A) Tl3+ > Tl+ (Stability order) (B) Pb2+ > Pb4+ (Stability order)
+ 2+ 3+
(C) Fe > Fe > Fe (Radius order) (D) O2– > F¯ > Na+ (radius order)

Q.159 Which of the following is only incorrect increasing order of first ionisation energy of the atoms or ions
mentioned?
(A) Mg+ < Al2+ < Na+ (B) I¯ < I < I+
(C) Li < B < Be (D) Br¯ < Cl¯ < F¯

Q.160 Which of the following case is affected by lanthanoid contraction according to their given properties?
(A) Stable oxidation state of thallium is +1. (B)Atomic radius of Zr ~ Hf.
(C) Ionisation potential of Tl > In (D) all of these

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Q.161 In which of the following, the energy change corresponds to first ionisation potential?
(A) X(g)  X+(g) + e– (B) 2X(g)  2X+(g) + 2e–
(C) X(s)  X+(g) + e– (D) X(aq)  X+(aq) + e–

Q.162 Out of N,O,Ne,Na and Na+, select the species which have minimum and maximum ionisation energy
respectively.
(A) N, Ne (B) O, Na+ (C) Na, Ne (D) Na, Na+

Q.163 The first ionisation enthalpies of four consecutive elements present in the second period of the periodic
table are 8.3, 11.3, 14.5 and 13.6 eV respectively. Which one of the following is the first ionisation
enthalpy of nitrogen ?
(A) 13.6 (B) 14.5 (C) 11.3 (D) 8.3

Q.164 Stability of ions of Ge, Sn and Pb will be in the order :

(A) Ge2+ > Sn2+ > Pb2+ (B) Ge4+ > Sn4+ > Pb4+
(C) Sn4+ < Sn2+ (D) Pb2+ < Pb4+

Q.165 M  X
M+  Y
M+2
Select the correct statement regarding the value of 'X':
(A) The value of 'X' is equal to ionisation potential of M.
(B) The value of 'X' is equal to magnitude of electron affinity of M+.
(C) Any information about 'X' can not |X| = |Y|
(D) Both option (A) and (B) regarding 'X' are correct.

Q.166 The correct order of ionisation energy among the following is :

(A) O > S > O– > S– (B) O > O– > S > S–
(C) O > S > S– > O– (D) S > O > S¯ > O¯
Q.167 Element which has maximum ionisation energy.
(A) Zn (B) Cu (C) Cd (D) Hg

Q.168 Element which has minimum first ionisation energyis -

(A) N (B) P (C) O (D) S

Q.169 For an element the successive ionisation energy values (in eV atom–1) are given below 12.32, 26.84,
44.56, 65.63, 203.9, 251.12, 308.4
The element that satisfies the above values is :
(A) Si (B) Ca (C)Al (D) S

Q.170 The ionisation energies for B, T and In are X,Y and Z Kcal/mol respectively, Choose the correct
relationship between them -
(A) Z > X = Y (B) X > Y > Z (C) X > Y = Z (D) X < Y > Z

Q.171 For an element having only one valence shell electron, then which of the following ionisation energy
difference will have the maximum value -
(A) IE2 – IE1 (B) IE3 – IE2 (C) IE3 – IE1 (D) can't predict

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Q.172 Which of the following represent second ionization energy?

(A) O(g)  O2+(g) + 2e– (B) O2 (g)  O22+ (g) + 2e–
(C) O+ (g)  O2+ (g) + e– (D)All of these

Q.173 The element having maximum tendencyto form ionic bonds is

(A) Cs (B) Rb (C) K (D) Li

Q.174 Which of the following has maximum ionisation energy?

(A) Li+ (B) He (C) Ne (D) Na

Q.175 The strongest reducing agent in gaseous phase is

(A) Li (B) Na (C) K (D) Cs

Q.176 M(g)  M+(g)  M+2(g) 

X
M+3(g)
IP 1 IP 2

IP1 X
The ratio of IP  2 . Then calculate the value of IP1 and IP2 if
2

M(g)   
 M+3(g), H = 5X
8X 4X 8X 4 X 2 4 X 2 8X 4X 8X
(A) , (B) , (C) , (D) ,
3 X 2 X 2X 2X 2X 2X 2  X 3 X

Q.177 The ionisation potential value for process M(g) — M(g) + is 'X'. Then choose the correct code if

ionisation potential value for M(g)— M(g) process is 'Y'.

–

(A) X = Y (B) X > Y (C) X < Y (D) Data Insufficient

ELECTRONAFFINITY
Q.178 Which process can produce maximum number of Fe2+ ions from iron atom by absorbing energy from
the given species.
Considering equal number of given species.
(A) Formation of N¯ from N-atom.
(B) Formation of F¯ from F-atom.
(C) Formation of Cl¯ from Cl-atom.
(D) Formation of S¯ from S-atom.

Q.179 In which of the following process, maximum amount of energyinvolved.

(A) Cl  Cl¯ (B) Br¯  Br (C) F¯  F (D) I¯  I

Q.180 Which of the following statement is correct.

(A) The 1st ionisation potential of N is greater than that of O+.
(B) The 1st ionisation potential of N is equal to that of O+.
(C) The 1st ionisation potential of N is less than that of O+.
(D) The electron affinity of ‘N’ is greater than that of ‘O’.

Q.181 Choose the correct order of the property given below :

(A) N3– < O2– : ionic radius (B) N > O : Ist ionisation energy
(C) N > O : 2nd ionisation energy (D) N > O : Electron affinity order
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Q.182 Calculate the value of electron gain enthalpy HEG) at 300 K if electron affinity of Cl is 90 Kcal.
(A) – 91.5 Kcal (B) + 88.5 Kcal
(C) –88.5 Kcal (D) – 1590 Kcal

 1
Q.183 The electron gain enthalpy (egH) of an element 'A' is    times of its ionisation enthalpy (iH).
 2
When one mole of A+(g) is completely converted into A–(g), 900 kJ heat is released. The egH of
element 'A' is :
(A) – 300 kJ/mol (B) – 600 kJ/mol (C) 600 kJ/mol (D) 300 kJ/mol

Q.184 If egH of A+ (g) = – x kJ/mol, egH of A(g) = – y kJ/mol and ionisationH of A+ (g) = +z kJ/mol, then
H for the process : A– (g)  A2+(g), is
(A) (x + y + z) kJ/mol (B) (z – x – y) kJ/mol
(C) (x + y – z) kJ/mol (D) (x – y + z) kJ/mol

Q.185 Which of the following are correct?

(I) 1st Ionisation Energy of N > O (II) 2nd Ionisation Energy of O > N
(III) 1st Electron Affinity of N < O (IV) 1st ElectronAffinity of Be < B
(A) I & II (B) I and III (C) I, II, III (D)All of these

Q.186 Which of the following would require least energy?

(A) Si– (g)  Si (g) + e– (B) P– (g)  P (g) + e–
(C) S (g)  S (g) + e
– – (D) Cl– (g)  Cl (g) + e–

Q.187 Which of the following represents correct order of electron affinity?

(A) O < S < F < Cl (B) O < F < S < Cl
(C) F > O > Cl > S (D) F > Cl > O > S

Q.188 Which of the following has the lowest electron affinity?

(A) O (B) S (C) F (D) Cl

Q.189 The incorrect order of electron affinity is :

(A) F < Cl (B) N > P (C) O < S (D) Cl > Br

Q.190 The first ionisation potential of Na is 5.1 eV. The value of electron gain enthalpy of Na+ would be
(A) –2.55 eV (B) –5.1 eV (C) –10.2 eV (D) 2.55 eV

Q.191 The least stable anion is :

(A) Li– (B) Be– (C) B– (D) C–

Q.192 The increasing order of electron affinityis :

(A) N < O < Cl < Al (B) O < N < Al < Cl (C) Al < N < O < Cl (D) Cl < N < O < Al

Q.193 Which is the correct order of ionisation energies?

(A) F¯ > F > Cl¯ > Cl (B) F > Cl > Cl¯ > F¯
(C) F¯ > Cl¯ > Cl > F (D) F¯ > Cl¯ > F> Cl
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Q.194 Which of the following statement is correct regarding following process.

Cl¯  Cl
I.E.
(i) Cl E

.A .
 Cl¯ (ii)
Cl+  Cl2+
I.E.
(iii) Cl I.E .
Cl+ (iv)
(A) | I.E. of process (ii) | = | E.A. of process (i) |
(B) | I.E. of process (iii) | = | I.E. of process (ii) |
(C) | I.E. of process (iv) | = | E.A. of process (i) |
(D) | I.E. of process (iv) | = | I.E. of process (iii) |

Q.195 Select incorrect order of E. A.

(A) Cl > F (B) O < S (C) N > P (D) C < Si

Q.196 Select correct relationship for Na atom.

(A) | I.E. of Na | < | E.A. of Na | (B) | I.E.of Na | > | I.E. of Na¯ |
(C) | I.E. of Na | > | I.E. of Na+ | (D) | E.A. of Na | = | I.E.of Na+ |

Q.197 The correct order of electron affinity is

(A) N > P > S > Cl (B) P > N > S > Cl
(C) Cl > N > P > S (D) Cl> S > P > N

Q.198 Choose the incorrect statement.

(A) 2nd electron gain enthalpy for any element is (+) ve.
(B) E.A. of an element  Zeff
(C) The ionisation energy order : F¯ > Cl¯
(D) The ionisation energy order : F¯ < Cl¯

Q.199 Which of the following statements is correct?

(A) Ionisation energy ofA¯ is greater thanA when Ais a halogen atom.
(B) Ionisation energy ofA+ is greater than that ofA2+ whenAis the member of alkali metals.
(C) Successive ionisation energy is always increasing for 1st and 2nd period element.
(D) Electron affinityvalue of 'A+' is numericallyidentical with the ionisation potential ofA¯
[for any atom].

Q.200 Which of the following is exothermic:

(A) N(g) + 1e–  N–(g) (B) P(g) + 1e–  P–(g)
(C) Na(g)  Na+(g) + 1e– (D) 1e– + Be(g)  Be–(g)

Q.201 In which transition maximum amount of energywill be released.

(A) S(g) + 1e–  S–(g) (B) O(g) + 1e–  O–(g)
(C) N(g)  N (g) + 1e
+ – (D) He(g) + 1e–  He–(g)

Q.202 Which of the following is incorrect order of electron affinity:

(A) Li < Na (B) Al > B (C) Si > C (D) Cl > F

Q.203 Which of the following process is endothermic?

(A) Na(g) + 1e¯ Na¯(g) (B) O+ (g) + 1e¯  O(g)
(C) O¯ (g) + 1e¯  O2– (g) (D) S + 1e¯  S¯(g)

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Q.204 Which of the following is incorrect?

(A) For A(g) + e–  A¯(g), H may be positive
(B) For A¯(g) + e–  A2–(g), H may be negative
(C) For A¯(g) + e–  A2–(g), H must be positive
(D) For A2+(g) + e–  A+(g), H must be negative

Q.205 If electron gain enthalpy of X(g) is – 4.0 eV, then the ionisation enthalpyof X(g) at the same temperature
may be :
(A) 4.0 eV (B) 3.5 eV (C) 5.5 eV (D) any of these values

Q.206 The correct order of increasing electron affinity of halogens is :

(A) F < Cl < Br < I (B) I < Br < F < Cl (C) I < Br < Cl < F (D) Br < I < F < Cl

Q.207 For the process

X(g) + e– X–(g), H = x and
X–(g) X(g) + e–, H = y
Select correct alternate :
(A) Ionization energy of X–(g) is y (B) Electron affinity of X(g) is –x
(C) Electron affinity of X(g) is +y (D)All are correct statements

Q.208 If the amount of energy required in the process X to X¯ is –5 kJ/mole then calculate how many energy
is required in X to X+ process
(A) –5 kJ/mole (B) > 5 kJ/mole (C) < 5 kJ/mole (D) 5 kJ/mole

Q.209 Which of the following speices has maximum tendency to accept electron cloud?
(A) O2– (B) O–1 (C) O+1 (D) O+2

Q.210 Select the correct order of electron affinity :

(A) F– > Cl– (B) F > Cl (C) Cl > F (D) F– > F

Q.211 The numerical value of energy involved in the given process ; S  S– is less than, which of the following
process :
(A) S–  S (B) Se  Se– (C) S  S+ (D) (B) and (C) both

Q.212 Which of the following process is exothermic ?

(A) P  P+ (B) P  P– (C) P–  P (D) P+  P+2

Q.213 Which is correct order of electron affinity?

(A) Li < Be (B) Be > B (C) Li > B (D) Li > C

Q.214 Which element has highest ElectronAffinity?

(A) Be (B) B (C) Li (D) C

Q.215 If the amount of energy required in the process X to X¯ is –8 kJ/mole then calculate how many energy
is required in X to X+ process
(A) –8 kJ/mole (B) > 8 kJ/mole (C) < 8 kJ/mole (D) 8 kJ/mole
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Q.216 Select the atom which has maximum electron affinity -

(A) C (B) Si (C) N (D) P

Q.217 Which of the following process is associated with the energy release.
(A) Li  Li+ (B) O¯  O2– (C) Cl +  Cl (D) Be  Be¯

ELECTRONEGATIVITY
Q.218 In which of the following process, maximum amount of energyinvolved.
(A) Cl  Cl¯ (B) Br¯  Br (C) F¯  F (D) I¯  I

Q.219 The most acidic oxide is :

(A) SO3 (B) P2O5 (C) Cl2O7 (D) P2O3

Q.220 The E.N. of H, X, O are 2.2, 3.0 and 3.5 respectively comment on the nature of the compound
H–O–X, that is :
(A) Basic (B)Acidic
(C)Amphoteric (D) Can't be predicted

Q.221 Find the incorrect acidic strength order:

(A) K2O > Rb2O > Cs2O (B) N2O < NO2 < N2O3
(C) Li2O < BeO < N2O5 (D) Cl2O7 > P2O5 > SiO2

Q.222 The correct order of electronegativity of C in C2H2, C2H4 and C2H6 is

(A) C2H2 > C2H6 > C2H4 (B) C2H2 > C2H4 > C2H6
(C) C2H6 > C2H4 > C2H2 (D) C2H4 > C2H2 > C2H6

Q.223 Ionisation energy and electron affinity of fluorine are respectively 17.42 eV and 3.45 eV, then
electronegativity of F atom on Pauling scale will be
(A) 10.44 (B) 4.0 (C) 3.72 (D) None of these

Q.224 Which of the following order is wrong.

(A) NH3 < PH3 < AsH3 – Acidic
(B) Li < Be < B < C – (IE)1
(C) Al2O3 < MgO < Na2O < K2O – Basic
(D) Li+ (g) < Na+(g) < K+(g) < Cs+(g) – Ionic radius

Q.225 Comment on the electronegativity (EN) ofAs inAsF3 andAsF5.

(A) E.N. of As (AsF3) > E.N. of As (AsF5)
(B) E.N. of As (AsF3) < E.N. of As (AsF5)
(C) E.N. of As is identical in both cases
(D) No comment can be predicted.

Q.226 Select the correct statement regarding oxides.

(A)As the electronegativity of element increase acidic character of oxide increases.
(B) Down the group the acidic nature of oxide increase.
(C) B2O3 and Al2O3 are both acidic oxides.
(D) Nitrogen forms all the three types of oxides (neutral, basic & acidic)

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Q.227 A student went to meet his friend, where he saw that his friend was doing the study of a particular
chemistry book. But he could not find the theoretical value of bond length in H-F but he found that rH &
rF are 0.37 Å and 0.72 Å respectively & electronegativity of F & H are 4.0 and 2.1 respectively.What
is bond length of H–F bond.
(A) 1.09 (B) 1.784 (C) 0.92 (D) 0.46

Q.228 Calculate the electronegativity of Cl in Pauling scale

[Given : E.A. (Cl) = 4.0 eV / atom and I.E. (Cl) = 13.0 eV / atom]
(A) 2 (B) 3.03 (C) 3.5 (D) 4.0

Q.229 Which of the following is strongest in basic character ?

(A) Be(OH)2 (B) Mg(OH)2 (C) Al(OH)3 (D) Si(OH)4

Q.230 For an inert gas element the atomic number is z, then which of the following element having atomic
number ‘___________’is having highest electronegativity.
(A) z – 2 (B) z – 1 (C) z + 1 (D) z + 2

Q.231 The electronegativityof ‘N’ is maximum in which of the following compound of N.

(A) N2O (B) N2O3 (C) NO (D) N2O4

Q.232 Which of the following acidic order is/ are correct.

(A) HI > HCl > HBr > HF (B) HI < HCl < HBr < HF
(C) HOCl > HOBr > HOI (D) HOCl < HOBr < HOI

Q.233 The correct order of Electronegativity is :

(A) F > O > N (B) N > O > F (C) O > N > F (D) N = O > F

Q.234 Which of the following statement is incorrect?

(A) Order of acidic strength N2O < N2O3 < NO2.
(B) ElectronAffinity of O is more than that of Cl.
(C) Percent ionic character of As – H bond is less than that of Sb–H bond.
(D)A 'sp' hybridised carbon is more Electronegative than a sp2 hybridised carbon.

Q.235 An element X has electronegativity of 3.0 on Pauling scale. Which of the statements is correct?
(A) The ionisation energy (IE) of X > 8.4 eV/atom
(B) The electron affinity (EA) of X > 8.4 eV/atom
(C) Both IE and EA > 8.4 eV/atom.
(D) Both IE and EA < 8.4 eV/atm.

Q.236 The bond energies of A –A, B – B and A – B bonds are 81, 100 and 115 Kcal/mol, respectively. If the
electronegativity of B is 3.0 and B is more electronegative than A, then from Pauling's Scale, the
electronegativity ofAis :
(A) 4.04 (B) 1.96 (C) 2.96 (D) 2.04

Q.237 The bond lengths ofA –Aand B – B bonds are 1.6 and 2.0 Å, respectively. If the electronegativities of
Aand B are 2.8 and 2.1, respectively, the according to Schomaker and Stevenson's Equation, the bond
length ofA – B bond should be :
(A) 3.537 Å (B) 2.97 Å (C) 1.737 Å (D) 1.17 Å
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Q.238 If X – Y bond is 30% ionic in character, then according to Hanny and Smyth Equation, the
electronegativity difference between X and Y is :
11
(A) 1.0 (B)
7
10 9
(C) (D)
7 7
Q.239 The correct order of acidic strength of these hydra acids is :
(A) HCl < HBr < HI < HF
(B) CH4 < SiH4 < GeH4
(C) NH3 < CH4 < H2O < HF
(D) HBr < H2S < NH3

Q.240 Which of the following is the most electropositive?

(A) Li (B) Na (C) K (D) Cs

Q.241 The most electronegative element is

(A) O (B) F (C) Cl (D) N

Q.242 Which of the following relations is correct? (E.N, is on Mulliken scale)

(A) 2 I.P. – E.A. – E.N. = 0
(B) 2 I.P. – E.N. + E.A. = 0
(C) 2 E.N. – I.P. – E.A. = 0
(D) E.N. – I.P. – E.A. = 0

Q.243 Calculate the percentage ionic character for moleculeAB, if electronegativity difference between AB
molecule is 1.5.
(A) 20.8 (B) 10.2 (C) 31.8 (D) None of these

Q.244 Ionisation energy and electron affinity of fluorine are respectively 18.42 eV and 2.45 eV, then
electronegativity of F atom on Pauling scale will be
(A) 3.72 (B) 4.0 (C) 10.44 (D) None of these

Q.245 Which of the following has maximum difference in bond length if the electronegativity difference is
considered and not considered?
(A) HCl (B) HF (C) HI (D) HBr

Q.246 Which of the following is amphoteric in nature?

(A) HClO4 (B) NaOH (C) Zn(OH)2 (D) N2O

Q.247 Which of the following is the most acidic in nature?

(A) SiO2 (B) P4O10 (C) CO2 (D) SO3

Q.248 The correct order of basic nature of given oxides is

(A) V2O3 < V2O5 < V2O4 (B) V2O3 < V2O4 < V2O5
(C) V2O5 < V2O4 < V2O3 (D) V2O5 < V2O3 < V2O4

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Q.249 Following is the graph representating Electronegativity of certain elementsA1,A2,A3 ,A4,A5. Which of
the following option(s) representing corresponding elements can be correct?

(A) A1 = N, A2 = P, A3 = F, A4 = Cl, A5 = Al
(B) A1 = Cl, A2 = P, A3 = O, A4 = N, A5 = Al
(C) A1 = N, A2 = P, A3 = O, A4 = Si, A5 = Al
(D) None

Q.250 Identify incorrect order of acidic strength :

(A) N2O < NO < N2O3 < N2O5 (B) CaO < CO < CO2
(C) H2O < Na2O < MgO (D) H2SO3 < H2SO4

Q.251 Find % covalent character of NO [Given: Electronegativity of N = 3 and O = 3.5]

(A) 8.875 % (B) 91.125 % (C) 20.2 % (D) 60.8 %

Q.252 Two elements Aand B are such that Bond energy of A–A, B–B & A–B are respectively 81 Kcal/mol,
64 Kcal/mol and 88 Kcal/mol. If electronegativity of B is 3 then electronegativity ofAmay be _____.
(A) 1.9 (B) 2.168 (C) 3.832 (D) 4.2

Q.253 Which is incorrect order of acidic strength?

(A) N2O < NO < N2O3 < NO2 (B) SO2 < SO3
(C) HOCl < HClO2 < HClO3 < HClO4 (D) CO2 < B2O3 < BeO < Li2O

Q.254 Which of the following is correct?

(A) Pauling scale is based on bond energy data.
(B) Muliken scale is based on IE and EA data
(C) Allred Roschow is based on electrostatic attraction.
(D) All are correct

Q.255 The order in which the following oxides are arranged according to decreasing basic nature is-
(A) CuO, Na2O, MgO, Al2O3 (B) Al2O3, MgO, CuO, Na2O
(C) MgO, Al2O3, CuO, Na2O (D) Na2O, MgO, Al2O3, CuO

Q.256 Identify the oxidation state of unknown element 'M' in following structure -
Electronegativity of H < Oxygen atom but M > Hydrogen atom
H
O
M H
O
O H
(A) + 5 (B) + 6 (C) + 3 (D) +4

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Q.257 On Muliken scale if electronegativity of particular atom 'X' is 'P' and electron affinityof atom 'X' is Q eV
then identify the approximate value of electronegativity of 'X' on Pauling scale -
2P  Q P
(A) (B) P × 2.8 (C) (D) (2P–Q) × 2.8
2 .8 2 .8

Q.258 Select the neutral oxide in following -

(A) CO2 (B) CO (C) P4O10 (D) NO2

Q.259 What will be the C–X bond length if C – C bond length is 1.54 Å, X – X bond length is 1.00 Å and
electronegativity values of C and X are 2.0 and 3.0 respectively.
(A) 2.45Å (B) 1.18 Å (C) 2.54 Å (D) 1.81 Å

Q.260 Which is amphoteric in nature.

(A) ZnO (B) Be(OH)2 (C) PbO2 (D)All of these

Q.261 An element has electronegativityon Mulliken Scale is 2.8 than what is the electronegativityof element on
All - Red Roschow Scale.
(A) 0.156 (B) 0.256 (C) 5.6 (D) 0.286

Q.262 On study it is seen that the electronegativity of the atom linearly increases with the partial ionic charge
(q). Thus electronegativity can be written as, x = a + bq, where large and soft atoms have low value of
b, while small and hard atoms have a large value of b, and a is constant, then which of the following given
plot describes the electronegativity variation of F and Cl accurately?
[Given : XF = 4, XCl = 3 and XH = 2]

x x x
F Cl F x F
4 4
3 4 Cl 4
Cl 3 F 3 Cl
2 3
(A) (B) 2 (C) 2 (D) 2

q q q
q

Q.263 Which of the following oxide is basic in nature?

(A) B(OH)3 (B) I(OH) (C) Cl(OH) (D) Cs(OH)

Q.264 Which of the following nitrogen oxide is neutral ?

(A) NO2 (B) N2O5 (C) N2O (D) N2O3

Q.265 Which of the following compound has maximum acidic character?

(A) CO2 (B) SiO2 (C) NH3 (D) H2O

Q.266 Calculate the bond length of P–Q molecule if internuclear distance of P2 is X and internuclear distance of
3X X
Q2 is and electronegative difference of P and Q element is .
2 2
3X
(A) (B) 1.20 X (C) 0.50 X (D) 0.20 X
2
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Q.267 Least stable hydride is

(A) stannane (B) Silane (C) Plumbane (D) Germane

Q.268 Calculate the % ionic character for metal fluoride where the electronegativityof electropositive element
is 2.1
(A) 43.03 % (B) 56.8 % (C) 50 % (D) 12 %

Q.269 Select the gas-phase reaction(s) which can proceed spontaneously?

(A) Cl¯ + I  I¯ + Cl (B) Si+ + Cl  Si + Cl+
(C) Both (A) & (B) (D) Kr + He+  Kr+ + He

Q.270 Comment on the electronegativity (E.N.) of P in PF3 and PF5.

(A) Electronegativity of P(PF3) > Electronegativity of P(PF5)
(B) Electronegativity of P(PF3) < Electronegativity of P(PF5)
(C) Electronegativity of P is identical in both cases
(D) No comment can be predicted

Q.271 The amphoteric oxide among the following is :

(A) Na2O (B) ZnO (C) SO2 (D) B2O3

Q.272 The correct order of acidic nature of the oxides of chlorine is :

(A) Cl2O < ClO2 < Cl2O6 < Cl2O7 (B) ClO2 < Cl2O < Cl2O6 < Cl2O7
(C) Cl2O < ClO2 < Cl2O7 < Cl2O6 (D) Cl2O7 < Cl2O6 < ClO2 < Cl2O

Q.273 Which one of the following is most acidic?

(A) SO3 (B) Cl2O7 (C) P2O5 (D) SiO2

Q.274 Calculate the % ionic character of molecule AB where the electronegative atom A is 3 and B is 2.1?
(A) 17.2 % (B) 19 % (C) 34 % (D) 50 %

Q.275 Which of following oxides is amphoteric in nature?

(i) ZnO (ii) N2O (iii) Cl2O7 (iv) BeO
(A) (i) ,(iv) (B) (i), (ii) (C) (iii) & (ii) (D) (i), (iv), (ii)

BORN HABER'S CYCLE

Q.276 Choose the correct ionic mobility order in water.
(A) Be2+ > Ba2+ (B) Li+ > Rb+ (C) I¯ < Cl¯ (D) Na+ > Mg2+ > Al3+

Q.277 The compound having least lattice energy is

(A) BeO (B) BaO (C) BeS (D) BaS

Q.278 Which of the following is incorrect order of the mentioned property in increasing order?
(A) First ionization potential : Na<Al<Mg<Si
(B) Ionization energy : Be+ < C+ < B+ < N+ < F+ < O+ < Li+
(C) Hydrated radius order : Ba2+ (aq) < Sr2+ (aq) < Mg2+(aq)
(D) Polarity order : N–H < Sb–H < As–H < P–H
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Q.279 The correct order of increasing hydration energy of following ion is

(A) Fe+2 < Co+2 < Fe+3 (B) Fe+2 < Co+2 > Fe+3
+2 +2
(C) Fe >Co > Fe +3 (D) Fe+2 < Fe+3 < Co+2

Q.280 Select the correct radius order :

(A) Li+(aq) < Na+(aq) < K+(aq) (B) Li+(g) < Be2+(g)
(C) Na(g) < Mg(g) < Al(g) (D) Li+(g) > Al3+(g)

Q.281 Choose the correct statement :

(A) Na+(g) > Mg2+(g) >Al3+(g) (Hydration energy)
(B) Li+(aq) < Na+(aq) < K+(aq)(Ionic Mobility)
(C) F–(aq) < Cl–(aq) < Br–(aq) (Hydrated radius)
(D) CaF2 > CaO(Lattice energy)

Q.282 Which of the following ions attach the least number of water molecules to itself when dissolved in water?
(A) Mg2+ (B) Li+ (C) [(CH3)4N]+ (D) NH 4

Q.283 The ion having highest mobilityin aqueous solution is :

(A) Be2+ (B) Mg2+ (C) Ca2+ (D) Ba2+

Q.284 Which of the following property increases down the group in a aqueous solution?
(A) Hydration energy (B) Ionic mobility
(C) Ionic size (D)All of these

Q.285 Given
Reaction Energy Change (in kJ)
Li(s)  Li(g) 161
Li(g)  Li (g)
+ 520
1
F (g)  F(g) 77
2 2
F(g) + e–  F–(g) (Electron gain enthalpy)
Li+(g) + F–(g)  LiF(s) –1047
1
Li (s) + F (g)  LiF(s) –617
2 2
Based on data provided, the value of electron gain enthalpy of fluorine would be :
(A) –300 kJ mol–1 (B) –228 kJ mol–1 (C) – 328 kJ mol–1 (D) –350 kJ mol–1

Q.286 Identify the correct order of conductivity in an aqueous solution.

[Where M is the d-block metal]
(A) [M(H2O)x]+2 > [M(H2O)y]+4 (B) [M(H2O)x]+2 < [M(H2O)y]+4
(C) [M(H2O)x]+2 = [M(H2O)y]+4 (D) we can not predict

Q.287 Choose the correct order of the following:

(A) Na+ (g) < Mg2+ (g) < Al3+ (g) : Hydration energy
(B) Mg2+(aq) > Sr2+ (aq) > Ba2+ (aq) : Hydrated radius order
(C) Mg2+(aq) > Sr2+ (aq) > Ba2+ (aq) : Ionic mobility order
(D) NaF > MgO > SrO : Lattice energy order
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Q.288 Which one of the following is correct sequence followed by molar ionic conductance of the ions in
aqueous solution.
(A) Li+ < Na+ < K+ < Rb+ (B) Rb+ < K+ < Na+ < Li+
(C) Sr2+ < Ca2+ < Mg2+ < Be2+ (D) Na+ < K+ < Li+ < Rb+

Q.289 Choose the correct statement

(A) Ionic mobilityAl3+ is greater than Mg2+ in water
(B) K+(aq) is having lesser ionic mobility than Ca2+(aq)
(C) Cl–(aq) is having highest ionic mobilityamong halide(aq) ions
(D) Ionic mobility of Cs+(aq) is the highest among the alkali metal ions

Q.290 The incorrect hydrated radius order is :

(A) Li+(aq) < Be2+(aq) (B) Na+(aq) < Al3+(aq)
(C) I–(aq) > Cl–(aq) (D) Ba2+(aq) < Ca2+(aq)

Q.291 The correct order of the lattice energy of the following hypothetical ionic compoundsAB,A2B &A2B3
where in all compounds B is in –2 oxidation state &Ahas variable oxidation state.
(A) A2B > AB > A2B3 (B) A2B3 > AB > A2B
(C) AB > A2B > A2B3 (D) A2B3 > A2B > AB

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EXERCISE-2 (OBJECTIVE QUESTIONS)

[MULTIPLE CORRECT CHOICE TYPE]

Q.1 For which of the following species the contribution of ‘s’ electron to the shielding constant is 0.3.
(A) H+ (B) He (C) Li+ (D) H¯

Q.2 Choose the correct statement.

(A) Be and Al are not in same group.
(B)All the transition metal ions are generallytypical Lewis acid
(C) Be andAl are having lot of similarities in their properties.
(D) The atomic radius gradually decreases from Sc to Zn.

Q.3 Which of the following is false

(A) Cr2+(g) ion has greater magnetic moment compared to Co3+(g).
(B) The magnitude of ionization potential of iron anion (monoanion) would be equal to electron gain
enthalpyof iron.
(C) lanthanide contraction is cause of lower I.P. of Pb than Sn.
(D) If successive ionization energy are 332, 738, 849, 4080, 4958 (in kJ/mol). Then this element can be
of 15th group.

Q.4 Which prediction/s is/are incorrect according to the Lother meyer curve.
(A) Each peak of the curve is occupied by the alkali metals.
(B)Alkaline earth metals occupy ascending position of curve
(C) Atomic volume increases first and then decreases in a period (which is defined later) in Lother
Meyer curve.
(D) Identically placed elements in the atomic volume v/s atomic mass curve, occur in the same period,
in the periodic table.

Q.5 Which of the following properties are the properties of metal.

(A) They are sonorous
(B) They are in general poor conductor of heat and electricity.
(C) They are malleable and ductile
(D) They are hard

Q.6 Four elements P, Q, R & S have ground state electronic configuration as:
P  1s2 2s2 2p6 3s2 3p3 Q  1s2 2s2 2p6 3s2 3p1
R  1s 2s 2p 3s 3p 3d 4s 4p
2 2 6 2 6 10 2 3 S  1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p1
Select the correct statement(s).
(A) size of P < size of Q
(B) size of R < size of S
(C) size of P < size of R (appreciable difference)
(D) size of Q < size of S (appreciable difference)

Q.7 Find the correct 2nd ionisation energy order from following option(s).
(A) Al > Mg (B) Te > Sb (C) Fe > Fe+ (D) In > Sr

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Q.8 The correct statements among the following are :

(A) Helium has the highest first I.P. in the periodic table.
(B) The process O(g) + e  O–2(g) is exothermic.
(C) The electron affinities of S and P are less than that of O and N respectively.
(D) In any period, the first ionisation potential of noble gas is the highest.

Q.9 Which of the following represents the correct order of the properties indicated?
(A) Ni2+ > Cr2+ > Fe2+ > Mn2+ (size)
(B) Sc > Ti > Cr > Mn (size)
(C) Ni2+ < Co2+ < Fe2+ < Mn2+ (unpaired electron)
(D) H3AsO4 > H3PO4 (Acidic strength order)

Q.10 The ionic radii depends upon the following factors

(A) charge of cation.
(B) charge of anion.
(C) Shell number of valence shell electron(s) of the ion.
(D) number of atoms for multiatomic ion.

Q.11 Which of the following pair(s) of elements is/are chemicallymost similar?

(A) Be, Al (B)Al, In (C) Ge, Sb (D) Ti, Hf

Q.12 Which of the following element/s have same value of shielding constant () for 3s-electron.
(A) Cr (B) Fe (C) Ar (D) Cl

Q.13 Which of the following ionisation energy order is correct.

(A) S > S¯ (B) O > S¯ (C) O > O¯ (D) S > O¯

Q.14 Choose the correct order of the following properties:

(A) Fe+3 (aq) > Fe2+ (aq) : Ionic mobility order
(B) Br¯ (aq) < Cl¯ (aq) < F¯ (aq) : Hydrated radius order
(C) SbH3 > AsH3 > PH3 : M–H bond polarity order
(D) S > C > H > B : Electronegativity order

Q.15 Which of the following set of elements are showing diagonal relationship.
(A) Na  Ca (B) Li  Mg (C) B  Si (D) N  P

Q.16 Which of the following is / are true.

(A) Multiplicity in Fe3+ is greater than that in Co3+.
(B) Ti3+, Cr+, Sc2+ ions are diamagnetic.
(C) Value of (n + l + m) for last electron of Mg is 3.
(D) The value of Zeff for 3s electron of Cl is 10.9.

Q.17 Which of the following statements is/are incorrect.

(A) Boron is diagonally related to magnesium.
(B) Bi5+ ion has smaller radius compared to Bi3+.
(C) last number of the seventh period of periodic table will have atomic number of 124 if discovered.
(D) Al2O3 is an amphoteric oxide.

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Q.18 Which of the following species is/are paramagnetic?

(A) Cr3+ (B) Cr6+ (C)Al3+ (D) O¯

Q.19 Select the correct statement(s).

(A)According to Mulliken, electronegativity is related to the average of the ionization energy and
electron affinity of the atom when they are expressed in eV / atom.
(B) Electronegativityof an atom having half filled electronic configuration will be more in general.
(C) HClO3 is stronger acid than HClO.
(D) Electronegativity goes on increasing with increase in atomic number in general as we move along a
period.

Q.20 Select the correct order of Ionic radii .

(A) Mn2+ > Mn4+ (B) Mn4+ > Mn2+ (C) N > N3– (D) N3– > N

Q.21 Which of the following set of molecules have same group.

(A) Ba, Ca, Na (B) In, Al, Tl (C) Sc, Ac, La (D) Ge, Ga, Se

Q.22 Which of the following Ist ionisation energy order is / are correct
(A) Be < B (B) N < O (C) Mg > Na (D) P > S

Q.23 Which of the following process is endothermic

(A) A2–  A¯ (B) A3+  A2+
(C) A  A
+ 3+ (D) A+ (ns2np6(n+)s1)  A2+

Q.24 Choose the incorrect hydration energy order:

(A) Li+ > H+ (B) H+ > Rb+ (C) Be2+ < Sr2+ (D) All are correct

Q.25 Which of the following term can be calculated from the Born-Haber cycle of formation ofAl2O3.
(A) Lattice energy of Al2O3 (B) Electron affinity of O-atom.
(C) Hydration energy ofAl3+ (D) Ionisation energy ofAl

Q.26 Choose the incorrect statement.

(A) 2nd electron gain enthalpy for any element is (+) ve.
(B) E.A. of an element  Zeff
(C) The ionisation energy order : F¯ > Cl¯
(D) All are correct

Q.27 When s is increases then which of the following periodic properties is/ are decreasing
(A) Electron gain enthalpy (B) Electronegativity
(C) Ionisation energy (D)Atomic radius

Q.28 Which of the following may represent the excited state of C–atom.
1s 2s 2p 3s 1s 2s 2p 3s
(A) (B)
1s 2s 2p 3s
(C) (D) None of these

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Q.29 Which of the following pairs of elements show diagonal relationship.

(A) Li – Mg (B) Be – Mg (C) Be – Al (D) B – Si

Q.30 Which of the following statements are correct?

(A) First ionisation energy (IE1) of Be is higher than that of B.
(B) Second ionisation energy (IE2) of O is higher than that of first ionisation energy of O.
(C) F is more electronegative than Cl.
(D) CH4 and SiH4 have all equal bond angles.

Q.31 Which of the following options have correct comparison of the radii of the species involved.
(A) Na > P (B) K > Si
(C) A–2 > A–1 > A+1 > A (D) Mg > Al+3

Q.32 Which of the following statements are correct :

(A) IE2 of Cu > IE2 of Zn where as IE1 of Cu < IE1 of Zn.
(B) |HEG | of S > |HEG| of O.
(C) Reducing nature of Li in aqueous solution is more than that of Na.
(D) There is a substantial contraction in size observed on moving from 3rd group to 4th group in 6th
period of periodic table.

Q.33 Which of the following order is correct?

(A) NH3 < PH3 < AsH3 : Acidic nature
(B) Li < Be < B < C : IE1
(C) Al2O3 < MgO < Na2O < K2O : Basic nature
(D) Li+ (g) < Na+(g) < K+(g) < Cs+(g) : Ionic radius

Q.34 Choose the incorrect statement(s) :

(A) Ionic mobility of Al3+ is greater than Mg2+ in water
(B) K+(aq) is having lesser ionic mobility than Ca2+(aq)
(C) Cl¯(aq) is having highest ionic mobilityamong halide(aq) ions
(D) Ionic mobility of Cs+(aq) is the highest among the alkali metal ions

Q.35 Identify correct statement(s) from the following?

(A) Diamond is the hardest natural substance
(B) H+ is the smallest cation of the periodic table.
(C) Metalloids are present only in p-block.
(D) O2– has fullyfilled configuration and hence energy will be released when O2–(g) is formed from O(g)
atom.

Q.36 Which of the following ions in ground state electronic configuration will behave as diamagnetic?
(A) Na+ (B) Mg+2 (C) Sc+1 (D) K+

Q.37 Select the correct statement :

(A)Atomic size ofAl is nearly equal toAtomic size of Ga.
(B) In Ist group from Na to Cs, Zeff remains constant
(C) If for an atom all the three types of radius can be measured then rvanderwall > rmetallic > rcovalent
(D) For the 3d-series elements, atomic radius remains almost constant.
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Q.38 Which statement/statements are true for Zn (30) ?

(A) Zeff for 3d electron is 8.85 (B) Zeff for 4s electron is 4.35
(C)  3d for Zn is 21.15 (D)  4s for Zn is 25.65

Q.39 The ionisation energy and electron affinityof an element is 12.9 eV/atom and 3.9 eV/atom, respectively.
The electronegativity of the element is :
(A) 3.0, on Pauling scale (B) 3.0, on Mulliken scale
(C) 8.4, on Pauling scale (D) 8.4, on Mulliken scale

Q.40 Which of the following is/are correct statement(s) ?

(A) In gaseous state, Cs is stronger reducing agent than Li.
(B) In gaseous atomic state, Chlorine is stronger oxidising agent than Fluorine.
(C) In gaseous molecular state, Fluorine is stronger oxidising agent than Chlorine.
(D) In gaseous state, Al should be stronger reducing agent than Mg, if both the gaseous atoms are
converting intoAl+(g) and Mg+ (g) ions, respectively.

Q.41 Which of the following is/are correct order?

(A) Acidic strength : HClO < HBrO < HIO
(B) Basic strength : Na2O > MgO > Al2O3 > SiO2
(C) Electron affinity : I < Br < F < Cl
(D) Ionisation energy : Cl– < Cl < Cl+

Q.42 The ionic compoundA+ B¯ is formed when the

(A) electron gain enthalpy of B is high (B) ionization energyofAis low
(C) lattice energy ofAB is high (D) lattice energy ofAB is low

Q.43 The correct order of atomic radii is

(A) N < Be < B (B) F– < O2– < N3– (C) Na > Li < K (D) Fe2+ > Fe3+ > Fe4+

Q.44 Which of the following do(es) not have higher ionisation energyas compared to their adjacent elements
across period?
(A)Al (B) Si (C) P (D) Cl

Q.45 Which of the following order is correct for first ionisation energy?
(A) Ga > Al (B) Na < Li (C) Be > Mg (D) F < Cl

Q.46 Which of the following process energyis liberated?

(A) Cl  Cl+ + e– (B) I + e–  I– (C) Cl + e–  Cl– (D) O– + e–  O2–

Q.47 Which option is/are not correct with respect to increasing order of atomic weight?
(A) Ar < K (B) Te < I (C) Th < Pa (D) Co < Ni

Q.48 Which of the folloiwng is correct?

(A) O has more electron affinity than Se.
(B) Cl has more electron affinity than F.
(C) F is most electronegative among Halogens.
(D) Ne has highest ionisation energy in periodic table.
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Q.49 Which of the following is correct regarding Ist ionisation energy?

(A) B > Al (B) Tl > In (C) Ga  Al (D) B < Tl

Q.50 Which of the following is/are correct order of first ionisation energy?
(A) P > S (B) Be > B (C) N > O (D) Li > Be

Q.51 Which of the following is/are correctly matched?

(A) F > O (Electronegativity) (B) Mg > Al (Ist ionisation energy)
(C) HCl > HI (Thermal stability) (D) Diamond > Graphite (Electrical conductance)

Q.52 Which of the following statements is/are incorrect?

(A) Ionisation energy ofA¯ is greater thanA when Ais a halogen atom.
(B) Ionisation energy ofA+ is greater than that ofA2+ whenAis the member of alkali metals.
(C) Successive ionisation energy is always increasing for 1st and 2nd period element.
(D) Electron affinityvalue of 'A+' is numericallyidentical with the ionisation potential ofA¯
[for any atom].

Q.53 Select the pair which follows energy order according toAufbau principle.
(A) 4f < 6s (B) 5d > 5p (C) 3d < 4d (D) 4s < 3s

Q.54 Select the classification which can explain same property of 'Li, Na, K'.
(A) Lavoisier Classification (B) Dobereiners Triad Law
(C) Newland Octave (D) Mendleev

Q.55 Select the element(s) which belongs to d-block but not transition elements
(A) Zn (B) Cd (C) Hg (D) Pt

Q.56 Degenerate orbital always have :

(A) n same (B) l same (C) m different (D) same shape

Q.57 Which of the following pairs were incorrectly arranged in Mendeleev's Periodic table?
(A) Ar - K (B) Te - I (C) Th - Pa (D) Co - Ni

Q.58 Which option is correct for atomic radius?

(A) Ne > F (B) Ar > Cl (C) F > Ne (D) Cl > Ar

Q.59 Choose the correct order of ionic size :

(A) Na+ > Mg2+ > Al3+ (B) Na+ < Mg2+ < Al3+ (C) N3– > O2– > F– (D) Pb2+ > Pb > Pb4+

Q.60 The species having 4 or more unpaired electrons are

(A) Fe2+ (B) Co3+ (C) Mn2+ (D) Ni2+

Q.61 Which option is / are correct?

(A) Atomic radius decreases with increase in Zeff
(B) The atomic number 50 element present in a 5th period
(C)Alkaline earth elements are IIAgroup elements
(D)Alkali metals are IAgroup elements.
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Q.62 Ionisation energy of an element is

(A) Equal in magnitude but opposite in sign to the electron affinity of the cation of the element.
(B) Same as electron affinity of the element
(C) Energy required to remove one valence electron from an isolated gaseous atom in its ground state.
(D) Equal in magnitude but opposite in sign to the electron affinity of the anion of the element.

Q.63 Which of the following ionisation energy order is/are correct :

(A) F > Cl– (B) F > Cl (C) Cl > F– (D) Cl– > F–

Q.64 Which of the following statement is incorrect?

(A) Order of acidic strength N2O < NO2 < N2O3
(B) Electron affinity of O is more than that of Cl.
(C) Percent ionic character of As–H bond is less than that of Sb–H bond.
(D)Amonoatomic cation is more electronegative than its parent atom.

Q.65 Which of the following gas - phase reactions can proceed spontaneously?
(A) Kr + He+  Kr+ + He (B) Si + Cl+  Si+ + Cl
(C) Cl + I  I + Cl
– – (D) Cl– + F  F– + Cl

Q.66 Mendlev left the space for elements in periodic table elements are :
(A) Ga (B) Sc (C) Ge (D) Tc

Q.67 If an element with atomic number 120 has discovered, then the correct information(s) regarding the
position of this element is modern long form of periodic table and its configuration is/are :
(A) It should belong form 8th period
(B) It's group number should be 2.
(C) It's ground state electronic configuration should be [Uuo] 8s2.
(D) It should have 28 electrons with l = 3, in the ground state.

Q.68 The increasing order of electron affinity.

(A) B < Al < O < S (B) Al < B < O < S (C) Al < B < S < O (D) Be < B < C < Si

Q.69 Which of the following is/are correct regarding p - orbital?

(A) Probability of finding a p-electron near nucleus is zero.
(B) There are three allowable values of magnetic quantum number (m)
(C) All p-orbitals are at 90° to each other.
(D) p orbitals have more penetration effect than s-orbital

Q.70 Within a given energy level order of energy can be :

(A) s > p > d > f (B) f > d > p > s (C) d > f > p > s (D) d = p = f = s

Q.71 The increasing order of atomic radius :

(A) O < N < S < P (B) Al < Se < Br < Ca
(C) Be < Li < Mg < Na (D) Al < Br < Se < Ca

Q.72 Which of the following set(s) all elements will have zero or negative electron affinity?
(A) Zn, Cd, Hg, N (B) Zn, Cd, Hg, P (C) He, Ne, Ar, Kr (D) F, Cl, Br, I
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Q.73 Which of the following is incorrect order of ionisation energy.

(A) Sc > Y > La (B) B > Al > Ga > In > Tl
(C) Li > Na > K (D) B > Be

Q.74 Which of the following set, have elements, which are havingsame number of electrons in their penultimate
shell?
(A) K, Na (B) Na, Mg (C) Rb, Sr (D) None of these

Q.75 In which of the following pair, size of first element is higher as compare to second.
(A) Sc, Zn (B) Ga,Al (C) N, F (D) Fe, Co

Q.76 Choose the correct ionisation energy order for the given species?
(A) O > S > S– > O– (B) F > F– > Cl– > Cl
(C) O > O– > S– > S (D) F > Cl > Cl– > F–

Q.77 Select the correct order according to their given properties.

(A) F > Cl > Br > I [Order of Electronegativity]
– – – –
(B) F > Cl > Br > I [Order of Hydrated radii]
(C) F– > Cl– > Br– > I– [Order of Ionic radii]
(D) F– < Cl– < Br– < I– [Order of Electrical conductivity]

Q.78 Select the incorrect statements:

(A) Halogens are at ascending part of the Lother-Mayer's atomic volume curve.
(B) Maximum number of elements possible in the 9th period of the periodic table are 50.
(C) As radius of Zn is greater than Cu so its ionisation energy is less than Cu.
(D)Ap-orbital can take maximum of six electron.

Q.79 Select correct statements among the following:

(A) The 1st IP ofAl is less than that of Ga
(B) The 2nd IP of oxygen is greater than 2nd IP of F
(C) The 2nd IP of lithium is less than 2nd IP of oxygen
(D) The EA1 of sodium is greater than EA1 ofAl

Q.80 Which of the following order is / are incorrect :

(A) O < Se < S [EA1 order ]
2– +
(B) O < Na < F¯ < Mg +2 [Ionic radius order]
(C) Li < Be < B < C [IE1 order]
(D) Cl < F < Br < I [EA1 order]

Q.81 Which of the following is / are Bridge elements?

(A) Na (B) K (C) Mg (D) Ca
Q.82 In which of the following elementsAufbau principle is violated?
(A) Cr (B) Cd (C) Cu (D) Co

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Q.83 The stable oxidation states of the element with the following values of successive ionisation energy will
be:
IE1 IE2 IE3 IE4 IE5 (eV/ atom)
18 26 46 54 65
(A) +1 (B) +2 (C) +4 (D) +5

Q.84 Choose the correct options :

(A) First Ionisation Energy of N > First Ionisation Energy of O - atom
(B) First Ionisation Energy of N  < First Ionisation Energy of O atom
(C) First Ionisation Energy of N < First Ionisation Energy of N  atom
(D) First Ionisation Energy of O < Second Ionisation Energy of O- atom

[PARAGRAPH TYPE]
Paragraph for question nos. 85 to 87
Electronegativity is important periodic property of the elements. It varies across the period and down the
group. There are certain reasons of its variation. It also affects the properties of the compounds.

Q.85 In which of the following hydrocarbons, carbon has highest electronegativity?

(A) C2H4 (B) CH4 (C) C2H2 (D) C2H6

Q.86 Which of the following oxide is most acidic?

(A) NO (B) N2O5 (C) N2O3 (D) NO2

Q.87 Which of the following species of Mn has lowest electronegativity?

(A) Mn(II) (B) Mn(IV) (C) Mn(VI) (D) Mn(VII)

Paragraph for question nos. 88 to 90

Electronic configuration (E.C.) of following elements are given as follows :
(I) 1s2 2s2 2p2 (III) 1s2 2s2 2p3
(II) 1s2 2s2 2p2 3s1 3p6 4s1 (IV) 1s2 2s2 2p0 3s2 3p6 3d1 4s2

Q.88 Select the correct set of block, group and period number for the above E.C. in periodic table.
Block Group Period Number
(A) Ip IVA 2
(B) II s IA 4
(C) III p VI A 2
(D) IV d IB 4

Q.89 Select the decreasing order of radius for the above E.C. in periodic table.
(A) II > I > IV > III (B) IV > III > II > I (C) II > IV > I > III (D) III > IV > II > I

Q.90 Select the decreasing order of electron affinity for the above E.C. in periodic table.
(A) II > III > I > IV (B) I > II > IV > III (C) II > I > IV > III (D) III > I > II > IV

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Paragraph for question nos. 91 to 93

Ionisation energy of the elements increases along the period and decreases along the group. Ionisation
energy of an element is numerically identical with electron affinity of the respective univalent cation.
Q.91 The first ionisation potential (in eV) of N, O atoms are:
(A) 14.6, 13.6 (B) 13.6, 14.6 (C) 13.6, 13.6 (D) 14.6, 14.6

Q.92 For the process

X (g) + e¯  X¯ (g) , H = x
and X¯ (g)  X (g) + e¯, H = y
Select correct alternate:
(A) Ionisation energy of X¯ (g) is y (B) Electron affinityof X(g) is x
(C) Electron affinity of X(g) is –y (D)All are correct statements

Q.93 Sodium forms Na+ ion but it does not form Na2+ because:
(A) Very low value of (IE)1 and (IE)2
(B) Very high value of (IE)1 and (IE)2
(C) Low value of (IE)1 and low value of (IE)2
(D) Low value of (IE)1 and high value of (IE)2

Paragraph for question nos. 94 to 96

The distribution of electrons in various shells, subshells and orbitals in an atom of an element, is called its
electronic configuration.
nlx
n = represent shell
l = represent subshell
x = number of electrons in subshell
Q.94 ns2 np4 electronic configuration of outermost shell correspond to which atomic number.
(A) 82 (B) 54 (C) 34 (D) 14

Q.95 Find the species having same number of d-electron in last possible filled d-subshell in Zn.
(A) Ga (B) Pd (C) Pt (D) None of these

Q.96 For the given electronic configuration the correct set of period number, group number & block is
respectively. 1s1 2s2 2p5 3s2 3p3 3d9 4s1 4p0
(A) 4, 3, d (B) 4, 5, d (C) 3, 13, p (D) 3, 1, s

Paragraph for question nos. 97 to 98

The electron affinity is a inherent property of the atom and it depends upon several factors.

Q.97 The correct electron affinity order is

(A) F > Cl (B) Cl > F (C) S < P (D) N > O

Q.98 Choose the incorrect statement.

(A) 1st I.E. ofA¯ is equal to electron affinity of A
(B) 2nd electron affinity is always greater than 1st electron affinity.
(C) O  O2– process is endothermic
(D) Li  Li+ process is endothermic.
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Paragraph for question nos. 99 to 101

The radius of an element can be measured in three ways, covalent radii (rc), metallic radii (rm) and
Vander Waal’s radii (rv) because they are not available in a single state. Ionic radii (ri) also measured
from their crystal lattices and it depends upon their different arrangement also.

Q.99 The radius of F and Ne are respectively (approximately).

(A) 1.6Å, 0.72Å (B) 0.72Å, 0.72Å (C) 0.72Å, 1.6Å (D) 1.21Å, 1.05Å

Q.100 Which of the following order is correct for the radii of the species.
(A) Fe3+ > Fe2+ (B) O 22  O 2 (C) S2– < Cl¯ (D) Ga >> Al

Q.101 For a particular element, the correct order of radii is

(A) rc < rv < rm (B) rc  rv > rm (C) rm > rv > rc (D) rv > rm > rc

Paragraph for question nos. 102 to 103

ElementsA,B,C,D and E are having the electronic configuration of:
A : 1s2 , 2s2 , 2p1
B : 1s2 , 2s2, 2p6 , 3s2 , 3p2
C : 1s2 , 2s2, 2p6 , 3s1
D : 1s2 , 2s2, 2p6 , 3s2 , 3p1
E : 1s2 , 2s2, 2p6

Q.102 Which among these will belong to same group in the periodic table.
(A) A and B (B) A and D (C) B and D (D) C and E

Q.103 The element havingmaximum ionisation energyis

(A) D (B) B (C) E (D) C

Paragraph for question nos. 104 to 106

From the following information
A– (g)  A+2 (g) + 3e– H1 = 1400 kJ/mole
A (g)  A (aq) + 2e
+2 – H2 = 700 kJ/mole
He.g[A+(g)] = – 350 kJ /mol
(IE1 + IE2) for A(g) = 950 kJ /mol

Q.104 Find the value of He.g of A2+ (g) in kJ / mole.

(A) + 600 (B) – 600 (C) – 500 (D) + 500

Q.105 Find the value of IE1 ofA¯ in kJ/mole.

(A) + 450 (B) + 350 (C) + 600 (D) + 250

Q.106 Find the Hhydration of A2+ (g) in kJ/mole.

(A) + 250 (B) – 350 (C) – 250 (D) – 300

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Paragraph for question nos. 107 to 109

Some of the properties which depend on electronic configuration of elements such as atomic radii,
ionisation potential, and electronegativity etc.

Q.107 The element with maximum electronegativitybelongs to

(A) Period 2, group 17 (B) Period 3, group 18
(C) Period 4, group 17 (D) Period 2, group 16

Q.108 In period, the ionisation energy is lowest for the

(A) Noble gases (B) Halogen
(C)Alkaline earth metals (D)Alkali metals

Q.109 The values of electronegativity of atoms A and B are 1.20 and 4 respectively. The percentage ionic
character of A – B bond is :
(A) 50% (B) 72.2% (C) 55.3% (D) 43.0%

Paragraph for question nos. 110 to 112

Ionization energy is the amount of energy required to knock out the most loosely bound electron in the
outer most shell in an isolated atom in the gaseous phase.
I.E1 = 40 eV / atom
I.E2 = 42 eV / atom
I.E3 = 200 eV / atom
Q.110 The element may belong to group
(A) 1st (B) 2nd (C) 13th (D) 14th

Q.111 The most stable oxidation state for the metal is

(A) +1 (B) +2 (C) +3 (D) +4

Q.112 Compare ionisation energy of X and X+.

X = 1s2 2s2
X+ = 1s2 2s1
(A) X+ > X (B) X > X+ (C) X+  X (D) None of these

Paragraph for question nos. 113 to 115

The minimum amount of energy which is required to remove an outermost electron from any isolated
neutral gaseous atom is known as first ionisation energy. These are the following factors which effect
ionisation energy.
1
(i) Ionisation Energy  principal quantum number

(ii) Ionisation Energy  Zeff

(iii)If orbitals are fully filled or half filled so stabilitywill be more and ionisation energy will
be high.
(iv) If penultimate electron will effectively shield the nucleus ionisation energy will be less and vise
versa.
Q.113 Choose the correct order of Ist ionisation energy.
(A) Ne < F (B) O > N (C) Na > Al (D) Mg > Al
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Q.114 Which of the following has maximum Ist ionisation energy?

(A) He (B) Mg (C) N (D) Na

Q.115 IE1 and IE2 of Mg are 178 kcal/mol and 348 kcal/mol. The enthalpy required for the reaction
Mg  Mg2+ + 2 e– is :
(A) +170 kcal/mol (B) +526 kcal/mol (C) – 170 kcal/mol (D) – 526 kcal/mol

Paragraph for question nos. 116 to 118

The ionisation energy (IE1) of an atom is defined as the energy needed to remove an electron from
gaseous atom in its ground state. The 2nd ionisation energy (IE2) is the additional energy needed to
remove the 2nd electron and so forth. The successive ionisation energyof anyspecie is increasing always.

Q.116 If the ionisation values of elements are plotted against atomic number, then peaks are occupied by
(A)Alkali metals (B)Alkaline earth metals
(C) Noble gas elements (D) Halogens

Q.117 The correct order of IInd ionisation energy is :

(A) Li > Ne > O (B) Ne > F > O (C) N > O > F (D) N > O > Li

Q.118 The Ist and IIIrd ionisation energy of an element is 20 eV and 50 eV respectively than IE2 is :
(A) 40 eV (B) 60 eV (C) 55 eV (D) 10 eV

Paragraph for question nos. 119 to 121

An atom is assumed to be spherical in shape and thus , the size of atom is generally given in terms of
radius of the sphere and is called atomic radius. It is usually defined as the distance between the centre
of the nucleus and outermost shell where electron or electrons are present. The exact measure of atomic
radius is not easy due to following reasons:
(i) The atom does not have well defined boundary. The probability of finding the electron is
never zero even at large distances from the nucleus.
(ii) It is not possible to get an isolated atom. The electron density around an atom is affected
by the presence of neighbouring atoms, i.e., the size of the atom changes in going from
one set of environment to another.
(iii) The size of an atom is very small, of the order of about 1.2 Å, i.e., 1.2 × 10–10 m.
An estimate of the size of the atom can, however, be made by knowing the distance between the atoms
in the combined state. The distance between the atoms, i.e., bond lengths are generally measured by the
application of techniques such as X-ray diffraction, electron diffraction, infrared spectroscopy, nuclear
magnetic resonance spectroscopy, etc. However, bond lengths change with different type of bonding.
Three types of radius are commonly used, i.e.,
(a) Covalent radius (b) Crystal radius (c) Vander Waal's radius

Q.119 The correct order of effective nuclear charge Zeff is

(A) Na < Mg < Al < Si < P (B) Na = Mg = Al = Si = P
(C) Na > Mg > Al > Si > P (D) None of these

Q.120 Choose incorrect option regarding atomic radius.

(A) F– < Cl– < H– (B) N3– > O2– > F¯
2+
(C) Fe < Fe 3+ (D) Fe2+ > Fe3+
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Q.121 Which of the following set of ions have the same value of screening constant for the valence electron,
calculated from Slater's rule?
(A) Li+, Na+, K+ (B) Na+, Mg2+, Al3+ (C) F¯, Cl¯, Br¯ (D) F¯, O2–, S2–

Paragraph for question nos. 122 to 124

The ionisation energy (IE1) of an atom is defined as the energy needed to remove an electron from
gaseous atom in its ground state. The 2nd ionisation energy (IE2) is the additional energy needed to
remove the 2nd electron and so forth. The successive ionisation energyof anyspecie is increasing always.

Q.122 Suppose a gas mixture of He, Ne,Ar and Kr is irradiated with photons of the frequency appropriate to
ionise Ne. What ions will be present in the mixture.
(A) He+ only (B) Ne+ only
(C) He+, Ne+, Ar+ only (D) Ne+, Kr+, Ar+ only

Q.123 If the ionisation values of elements are plotted against atomic number, then peaks are occupied by
(A)Alkali metals (B)Alkaline earth metals
(C) Noble gas elements (D) Halogens

Q.124 The numerical value of energy involved in the given process; Na  Na¯ is less than that of which of
the following processes.
(A) Na¯  Na (B) Na  Na+
(C) Both (A) & (B) (D) None of these

Paragraph for question nos. 125 to 127

Over view of long form of periodic table is as shown in which seven period and eighteen groups are
present.
IUPAC
Group No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Period
st
1 Period

nd
2 Period

rd
3 Period

th
4 Period

th
5 Period

th
6 Period

th
7 Period

Q.125 If same structure will maintain for further discovery of new elements, then what is the maximum number
of elements that can be accomodated by 10th period of periodic table?
(A) 18 (B) 36 (C) 72 (D) 90
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Q.126 If each orbital can hold a maximum of 3 electron. The number of elements in 4th period of periodic table
is :
(A) 48 (B) 57 (C) 27 (D) 36

Q.127 Element with atomic number 58 belongs to which IUPAC group number in the periodic table.
(A) 1 (B) 2 (C) 3 (D) 4

Paragraph for question nos. 128 to 130

The force of attraction exerted by the nucleus on a given electron is decreased due to repulsion caused
by the intervening electrons. The net force of attraction is represented by Zeff where Zeff = Z – .

Q.128 The value of Zeff is minimum for

(A) Li (B) Na (C) K (D) Same for all

Q.129 The value of  for 5s electron of Rb37 is

(A) 2.2 (B) 34.8 (C) 27.9 (D) None of these

Q.130 The force of attraction exerted the nucleus will be maximum on:
(A) 4s (B) 4p (C) 4d (D) 4f

[MATCH THE COLUMN]

Q.131 Column I Column II

(A) N, F, O, Li (P) Increasing order of | EA |
(B) F, N, Si, Mg, Rb (Q) Increasing order of IE1
(C) K, Na, Al, Mg (R) Increasing order of IE2
(D) N, B, O, Cl (S) Increasing order of radius

Q.132 Match the column :

Column-I Column-II

(A) Ni (P) Elements having same number of unpaired electron in

their dipositive ion in column I.

(B) K (Q) At least 13 electrons are having magnetic

quantum number 'zero'.

(C) Mn (R) Atom is paramagnetic.

(D) Pd (S) Element is not transition element

(T) Element having pseudo inert gas configuration in

its dipositive cation.
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Q.133 Column I Column II

(Atomic Number)
(A) 57 (P) d-Block or p-Block
(B) 17 (Q) 4th Period element
(C) 19 (R) ViolatesAufbau's Principle
(D) 29 (S) Not lanthanides

Q.134 Match the column:

Column I Column II
(A) Zinc (P) Solid at room temperature
(B) Hg (Q) Transition element
(C) Cr (R) d-block element
(S) Liquid at room temperature

Q.135 Column I Column II

(Characteristic involved in the (Process described)
given process of Column II)
(A) Energy released (P) S  S¯
(B) Energy absorbed (Q) O¯  O2–
(C) Inert gas configuration is achieved (R) Sr  Sr2+
(D) Half filled configuration is achieved (S) N¯  N
(T) Ge  Ge¯

Q.136 Column I Column II

(A) Si (P) Having diagonal relationship with B
(B) He (Q) p-block element
(C) O (R) Two unpaired electrons present in its ground state
(S) Having highest ionisation energy.

Q.137 Column I Column II

(A) Cl (P) Non transition element
(B) Be (Q) Having highest electronegativityamong the three.
(C) Cd (R) Element which is present in II B group
(S) Element which is first element of its group.

Q.138 Column I Column II

(Set of substances) (Characteristic the set)
(A) Ag+ , Cd+2, Sn+4 (P) Corresponding elements are representative elements.
(B) F, Br, Cl (Q) Isoelectronic species.
(C) Li, Na, K (R) Corresponding elements will lie on similar positions in
Lothermeyer's curve.
(D) +2 +2
Ba , Sr , La +1 (S) Arranged in increasing order of size.
(T) At least one of the corresponding elements belong to
different block.
[Given Data : Sr (Z = 38) , Ba (Z = 56), Ag (Z = 47), Cd (Z = 48), Sn (Z = 50)]

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Q.139 Column I Column II

(A) K (P) s-block element
(B) Mg (Q) element of 4th period
(C) Cr (R) d-block element
(D) Zn (S) transition element
(T) all the electrons are paired

Q.140 Column-I Column-II

(Number of Elements) (Period number of modern
long form of periodic table)
(A) 8 (P) 2
(B) 18 (Q) 3
(C) 32 (R) 5
(S) 6

Q.141 Column I Column II

(A) Na+, Na, Na– (P) Increasing order of radius
(B) B, C, N (Q) Decreasing order of I E
(C) F–, Cl–, Br–, I– (R) Same number of outermost shell electrons
(D) Be, Mg, Ca (S) Same principal quantum number 'n' for the
outermost shell containing electron(s).
(T) increasing order of total electrons

Q.142 Column-I Column-II

(A) Be (P) Bridge element
(B) Al (Q) Element having diagonal relationship
(C) O (R) Have unpaired electron
(D) Fe (S) Transition element
(T) Have no unpaired electron

Q.143 List -I List - II

(P) Total number of s-block elements (1) 14

(Q) Maximum number of electrons in some spin in (2) 15

the ground state of Chromium(Z = 24)

(R) Number of metalloid in group-13 of the modern (3) 0

long form of periodic table

(S) Effective nuclear charge for 3p- electron in the (4) 14.75
ground state of iron (Fe = 26), as per Slater's rule.
Codes :
P Q R S
(A) 4 2 1 3
(B) 1 3 2 4
(C) 2 1 3 4
(D) 1 2 3 4
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Q.144 Column I Column II

(A) Atomic Number = 7 (P) It belong to d-block
(B) Atomic Number = 21 (Q) Normal element
(C) Atomic Number = 16 (R) It can have magnetic quantum number value m = –2
(D) Atomic Number = 29 (S) If each orbital is occupy by 3-electrons then
It belong to p-block
(T) It have total number of even electron which has
1
l = 1 and s = 
2

Q.145 Column I Column II

(A) He (g) > H (g) (P) Ist ionisation energy
(B) Li+ (g) < Be+2 (g) (Q) Tendency to gain an electron
(C) O(g) > P (g) (R) Electronegativity
(S) Effective nuclear charge value

Q.146 Column I Column II

(A) N (P) Paramagnetic
(B) Cu+ (Q) Diamagnetic
(C) Fe (R) p-block
(D) O (S) d-block
(T) Partiallyfilled d-orbitals

[INTEGER TYPE]

Q.147 The IE1, IE2, IE3, IE4 and IE5 of an element are 7.1, 14.3, 32.5, 46.8 and 162.2 eV respectively. The
stable oxidation state of the element is _______.

Q.148 Calculate the Zeff (approx) for 4s electron of Ni-atom according to Slater's rule.

Q.149 Calculate experimental bond moment (Approximate, in Debye) of A– B bond. If electronegativity of

element A & B is 2 and 3.5 respectively & bond length is 3.92 Å.

Q.150 If there were 9 periods in the periodic table & each orbital can have maximum 5 electrons, then how
many maximum number of elements will be present in period 9?

Q.151 Calculate the value of Zeff on 3d electron of Sc?

Q.152 How many elements from the following are not transition element?
Zr, Co, Cd, Hg, Au, Cu

Q.153 The amount of energy released when one million atoms of iodine in vapour state are converted to I– ions
is 4.9 × 10–13 J. What is the electron affinity of Iodine in eV per atom.

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Q.154 Given
Bond energy of F – F bond = 38 Kcal / mol–1
Bond energy of Cl – Cl bond = 58 Kcal / mol–1
Bond energy of Cl – F bond = 61 Kcal / mol–1
Electronegativity of fluorine = 4 eV
Calculate the electronegativityof chlorine atom.

Q.155 Calculate the Zeff on the electron present in 5d-orbital of Gd (Atomic number = 64).

Q.156 Calculate the Zeff of 39th electron of Y (Yttrium).

Q.157 Find the total number of species having magnetic moment value of 2.84 B.M. from following species.
Fe2+, Cr, Cr3+, Ti2+, Mn2+, V3+

Q.158 Find the total number of low shielding electrons in Hg2+ ions.

Q.159 Find the number of 'p' block elements from the following atomic numbers given below.
83 79 42 64 37 54 34

Q.160 Find the total number of electron in d-orbital.

Q.161 The number of p block elements accordingly to following configuration is __________.

1s22s22p6, 1s22s2, 1s22s22p63s2 3p63d104s2, 1s22s22p63s2 3p1

Q.162 The number of electrons present in the s-subshell within Mn.

Q.163 The value of  (screening constant) for 3s electron of P is 10.5 then what is value of  for 3p electron
of S.
[If your answer is 3.45 then write 0345]
(Note : change 10.5 to x and Answer would be x + 0.35 )

Q.164 The internuclear distance (x Å ) between C and H in C–H bond is determined by using Schomaker &
Stevenson equation . If internuclear distance between the two carbon atoms in C–C bond is 2.4 Å and
between the two hydrogen atoms in H–H bond is 0.8Å. Given Electronegativities of C and H are 2.4
and 2.1 respectively. Calculate the value of 1000x.

Q.165 The number of process that are definitely exothermic (Energy is released) out of the following
processes are :
(i) 2Cl(g)  Cl2(g) (ii) Na+(g) + F(g) + e–  NaF(s)
(iii) Cl(g) + H2O + e–  Cl–(aq) (iv) Al+2(g) + e–  Al+1(g)
(v) P(g) + e  P (g)
– – (vi) Ne(g) + e–  Ne–(g)
(vii) Hf of H+(g) (viii)A(s) A(g) whereAis any element

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Q.166 BF3 has the following structure . If covalent radius of B is 0.85 Å and that of F is 0.73 Å and

100 Y
electronegativity of B is 2 and F is 4 then calculate the value of where Y is the intermolecular
3
distance between two fluorine atoms in Å.

Q.167 Given : H EG of A+ = – 5x
H EG of A2+ = – 8x
H IE of A2+ = 15x
H EG of A4+ = – 23x
If the enthalpy change in the given process A+ (g) A4+(g) isH = ax
Then 'a' will be

Q.168 Calculate the sum of "Code numbers" of all the cases in which correct order of the mentioned parameter
is represented.
S.No. Order Parameter Code Number

1. Na < Cl < F Electronegativity 28

2. Be < Mg < Na Metallic character 53
3. Al3+ > Mg Ionic radius 14
4. O < F < Cl | HEG| 8
5. Cl2O7 > Al2O3 > Na2O Basic nature of oxide 59
For example if S.No. (3) & (5) are correct your answer should be 59 + 14 = 73 therefore fill
0073.

Q.169 Calculate sum of code numbers of all those orders which are incorrectly written.
S.No. Parameter Order Code No.
1. Ionisation energy (IE1) O¯> S¯ 58
2. Atomic Size Mg > Cl > Si 22
3. Acidic nature of oxides Na2O < H2O < CO2 < SO3 46
4. Number of unpaired electron Na+ < Fe2+ < Cr < Mn 113

Q.170 The outermost shell of an element has only one electron in the ground state. If the outermost shell is the
'N' shell, then the minimum and maximum atomic numbers for the element is/are :
[If the minimum and maximum atomic numbers are 9 and 45, then fill the OMR as 0945]

Q.171 If Q = Zeff of the 26th electron of Fe then find out the value of 100 × Q ?

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Q.172 The difference in atomic numbers of the inert gas and alkali metal in the 5th period of the modern long
form of periodic table is

Q.173 The ratio of 1st, 2nd and 3rd ionisation enthalpies of A– (g) is 1 : 3 : 12. If H for the process :
A2+ (g)  A– (g) is – 320 Kcal/mol, then the 2nd ionisation enthalpy of A(g) (in Kcal/mol) is :

Q.174 The species having one or more unpaired electron are paramagnetic.Among the following ions :
Cu2+, Zn2+ , Fe2+ , Ni2+, Cr3+, Co3+, Sc3+, Ti4+
the number of paramagnetic ions is :

Q.175 Read the following statements :

(i) The number of unpaired electrons in ground state of N-atom is 'x'
(ii) The maximum number of unpaired electrons in parallel spin in the ground state of Ni - atom is 'y'
(iii) The minimum number of electrons in parallel spin in the ground state of Cr-atom is 'z'.
The sum of (x + y + z) is :

Q.176 According to Pauling, the percentage ionic character inA–B molecule may be given as :
Percent ionic character = 18 (XB – XA)1.4
Where XB and XA are electronegativities of B and A, respectively and XB > XA. If XA = 1.84 and
XB = 3.48, then the percentage ionic character in A–B is (Given : (2)5/7 = 1.64)

Q.177 For an element, the metallic radius is 20% greater than its covalent radius. If the metallic radius of the
element is 180 pm, then its covalent radius (in pm) is :

Q.178 Among the following compounds, the number of compounds having greater magnitude of lattice energy
than RbBr, are
NaCl, KF, RbCl, CsBr, NaBr, KCl, CsI, RbI.

Q.179 If therewere more periods in the modern long form of the periodic table, then the maximum number of
elements in the 9th and 10th period should be (If number of elements in 9th and 10th period are 36 and
8, respectively, then answer as 3608)

Q.180 Find the group number of element 'X' which belongs to s- or p- block, having successive ionisation
energies as per the graph gives below :

35
30

IE
(ev)
12

IE1 IE2 IE3 IE4

Successive Ionisation

If your answer is group-I, write it as 0001.

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Q.181 Find the total number of species having two unpaired electron from the following species.
Fe2+, Cr, Cr3+, Ti2+, Mn2+, V3+
[If your answer is 9 then write the answer as 0009]

Q.182 Find the difference(magnitude) in effective nuclear charge between a 3d electron of Ni (Z = 28) and a 2p
electron of oxygen.

Q.183 Find the total number of elements which have higher ionisation energy than their both adjacent elements
(either in a period or in a group in the long form of periodic table.)
Be, B, N, P, Ga, S, Mg

Q.184 What is the atomic number of element having IUPAC name 'Uub'?

Q.185 The magnetic moment value of species 'X' is 4.8 B.M. Find out the number of unpaired electrons in 'X'.

Q.186 From the given compounds if 'X' number of compounds which are acidic in water.
Li2O, SiO2, Cl2O7, B2O3, Cr2O3, CO, CO2, SO3, MgO, Al2O3
then find the value of 'X'

Q.187 For atom 'A' ionisation energy is given in eV :

I.E.1 I.E.2 I.E.3 I.E.4 I.E.5
11.2 24.3 37.4 48.4 392.0
How many electrons are present in valance shell of that atom?

Q.188 For X5+ ion, the successive electron affinities (in eV) are 289.7, 270.9, 30.1, 17.9 and 8.3. The expected
number of electrons in the outermost shell of X-atom is

Q.189 From the given compounds if 'X' number of compounds which are acidic in water.
Li2O, SiO2, Cl2O7, B2O3, Cr2O3, CO, CO2, SO3, MgO, Al2O3
then find the value of 'X'

Q.190 How many following total number of process are endothermic -

O  O– N   N– Cl+ 
 Cl
N  N+ Ne   Ne+ P  P+
S 
 S+ Be   Be+ Se  Se–2

Q.191 What will be the difference of Zeff in 11Na and 19K for last electron -

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EXERCISE-3
SECTION-A
(JEE Main Previous Year's Questions)

Q.1 The correct order of atomic radius is - [AIEEE-2002]

(A) Ce > Sm > Tb > Lu (B) Lu > Tb > Sm > Ce
(C) Tb > Lu > Sm > Ce (D) Sm > Tb > Lu > Ce

Q.2 Ce3+, La3+, Pm3+ and Yb3+ have ionic radii in the increasing order as – [AIEEE-2002]
(A) La3+ < Ce3+ < Pm3+ < Yb3+
(B) Yb3+ < Pm3+ < Ce3+ < La3+
(C) La3+ = Ce3+ < Pm3+ < Yb3+
(D) Yb3+ < Pm3+ < La3+< Ce3+

Q.3 According to the Periodic Law of elements, the Variation in properties of elements is related to their ?
[AIEEE-2003]
(A) Nuclear masses (B)Atomic numbers
(C) Nuclear neutron-proton number ratio (D)Atomic masses

Q.4 The reduction in atomic size with increase in atomic number is a characteristic of elements of -
[AIEEE-2003]
(A) d-block (B) f-block
(C) Radioactive series (D) High atomic masses

Q.5 Which one of the following groups represent a collection of isoelectronic species ?
(At. no. Cs = 55, Br = 35) [AIEEE-2003]
3– – + 3+ –
(A) N , F , Na (B) Be, Al , Cl
2+ +
(C) Ca , Cs , Br (D) Na+, Ca2+, Mg2+

Q.6 The atomic numbers of vanadium (V). Chromium (Cr), manganese (Mn) and iron (Fe) respectively 23,
24, 25 and 26. Which one of these may be expected to have the higher second ionization enthalpy ?
[AIEEE-2003]
(A) Cr (B) Mn (C) Fe (D) V

Q.7 Which one of the following sets of ions represents the collection of isoelectronic species ?
[AIEEE-2004]
+ – 2+
(A) K , Cl , Mg , Sc 3+ + 2+
(B) Na , Ca , Sc , F 3+ –
+ 2+ 3+
(C) K , Ca , Sc , Cl – (D) Na+, Mg2+, Al3+, Cl–

Q.8 Which one of the following ions has the highest value of ionic radius ? [AIEEE-2004]
(A) O2– (B) B3+ (C) Li+ (D) F –

Q.9 Among Al2O3, SiO2, P2O3 and SO2 the correct order of acidic strength is : [AIEEE-2004]
(A) Al2O3 < SiO2 < SO2 < P2O3 (B) SiO2 < SO2 < Al2O3 < P2O3
(C) SO2 < P2O3 < SiO2 < Al2O3 (D) Al2O3 < SiO2 < P2O3 < SO2

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Q.10 The formation of the oxide ion O 2g requires first an exothermic and then an endothermic step as shown
below. [AIEEE-2004]
O(g) + e– = O–(g) H° = – 142 kJ mol–1
O–(g) + e– = O2–(g) H° = 844 kJ mol–1
This is because of :
–
(A) O ion will tend to resist the addition of another electron
(B) Oxygen has high electron affinity
(C) Oxygen is more electronegative
(D) O– ion has comparatively larger size than oxygen atom

Q.11 In which of the following arrangements the order is NOT according to the propertyindicated against it ?
(A) Al3+ < Mg2+ < Na < F– – increasing ionic size [AIEEE-2005]
(B) B < C < N < O – increasing first ionization enthalpy
(C) I < Br < F < Cl – increasing electron gain enthalpy (with negative sign)
(D) Li < Na < K < Rb – increasing metallic radius
Q.12 Which of the following oxides is amphoteric in character ? [AIEEE-2005]
(A) SnO2 (B) SiO2 (C) CO2 (D) CaO
Q.13 The lanthanide contraction is responsible for the fact that [AIEEE-2005]
(A) Zr and Y have about the same radius (B) Zr and Nb have similar oxidation state
(C) Zr and Hf have about the same radius (D) Zr and Zn have the same oxidation state

Q.14 The increasing order of the first ionization enthalpies of the elements B, P, S and F (lowest first) is –
[AIEEE-2006]
(A) F < S < P < B (B) P < S < B < F (C) B < P < S < F (D) B < S < P < F
Q.15 Which one of the following sets of ions represents a collection of isoelectronic species ? [AIEEE-2006]
(A) N3–, O2–, F–, S2– (B) Li+, Na+, Mg2+, Ca2+
+ – 2+
(C) K , Cl , Ca , Sc 3+ (D) Ba2+, Sr2+, K+, Ca2+
Q.16 In which of the following arrangements, the sequence is not strictly according to the property written
against it ? [AIEEE-2009]
(A) H2O < H2S < H2Se < H2Te : Increasing acidic strength
(B) HF < HCl < HBr < HI : Increasing acidic strength
(C) NH3 > PH3 < AsH3 < SbH3 : Increasing basic strength
(D) B < C < O < N : increasing first ionization enthalpy

Q.17 The set representing the correct order of ionic radius is – [AIEEE-2009]
+ 2+ + 2+ + + 2+ 2+
(A) Li > Be > Na > Mg (B) Na > Li > Mg > Be
2+ + 2+ 2+
(C) Li > Na > Mg > Be (D) Mg2+ > Be2+ > Li+ > Na+

Q.18 The correct sequence which shows decreasing order of the ionic radii of the elements is
[AIEEE-2010]
3+ 2+ + – 2–
(A) Al > Mg > Na > F > O (B) Na > Mg > Al > O > F–
+ 2+ 3+ 2
+ – 2+ 2– 3+
(C) Na > F > Mg > O > Al (D) O2– > F– > Na+ > Mg2+ > Al3+

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Q.19 Which one of the following ordered presents the correct sequence of the increasing basic nature of the
given oxides ? [AIEEE-2011]
(A) Al2O3 < MgO < Na2O < K2O (B) MgO < K2O < Al2O3 < Na2O
(C) Na2O < K2O < MgO < Al2O3 (D) K2O < Na2O < Al2O3 < MgO

Q.20 The increasing order of the ionic radii of the given isoelectronic species is [AIEEE-2012]
(A) Ca2+, K+, Cl–, S2– (B) K+, S2–, Ca2+, Cl–
(C) Cl–, Ca2+, K+, S2– (D) S2–, Cl–, Ca2+, K+

Q.21 The first ionisation potential of Na is 5.1 eV. The value of electron gain enthalpy of Na+ will be:
(A) –5.1 eV (B) –10.2 eV (C) +2.55 eV (D) –2.55 eV
[JEE Main - 2013]

Q.22 Which of the following represents the correct order of increasing first ionization enthalpy for Ca, Ba, S,
Se and Ar? [JEE Main - 2013]
(A) S < Se < Ca < Ba < Ar (B) Ba < Ca < Se < S < Ar
(C) Ca < Ba < S < Se < Ar (D) Ca < S < Ba < Se < Ar

Q.23 The ionic radii (in Å) of N3–, O2– and F– are respectively ?
(A) 1.71, 1.40 and 1.36 (B) 1.71, 1.36 and 1.40
(C) 1.36, 1.40 and 1.71 (D) 1.36, 1.71 and 1.40
[JEE Main 2015]

Q.24 Which of the following atoms has the highest first ionization energy ? [JEE Main 2016]
(A) Sc (B) Rb (C) Na (D) K

Q.25 The group having isoelectronic species is : [JEE Main 2017]

(A) O¯, F¯, Na, Mg+ (B) O2–, F¯, Na, Mg2+
(C) O¯, F¯, Na+, Mg2+ (D) O2–, F¯, Na+, Mg2+

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SECTION-B
(JEE ADVANCED Previous Year's Questions)

Q.1 Moving from right to left in a periodic table, the atomic size is: [JEE 1995]
(A) increased (B) decreased (C) remains constant (D) none of these

Q.2 The increasing order of electronegativity in the following elements: [JEE 1995]
(A) C, N, Si, P (B) N, Si, C, P (C) Si, P, C, N (D) P, Si, N, C

Q.3 One element has atomic weight 39. Its electronic configuration is 1s2, 2s2 2p6, 3s2 3p6 4s1. The true
statement for that element is:
(A) Highest value of IE (B)Transition element
(C) Isotone with 18Ar38 (D) None [JEE 1995]

Q.4 The number of paired electrons in oxygen atom is: [JEE 1995]
(A) 6 (B) 16 (C) 8 (D) 32

Q.5 The decreasing size of K+, Ca2+, Cl– & S2– follows the order: [REE 1995]
(A) K+ > Ca +2 > S–2 > Cl– (B) K+ > Ca +2 > Cl– > S–2
(C) Ca +2 >K+ > Cl– > S–2 (D) S–2 > Cl– > K+ > Ca+2

Q.6 Which of the following oxide is neutral? [JEE 1996]

(A) CO (B) SnO2 (C) ZnO (D) SiO2

Q.7 Which of the following has the maximum number of unpaired electrons [JEE 1996]
(A) Mg2+ (B) Ti3+ (C) V3+ (D) Fe2+

Q.8 The following acids have been arranged in the order of decreasing acid strength. Identify the correct
order : ClOH(I) BrOH(II) IOH(III) [JEE 1996]
(A) I > II > III (B) II > I > III (C) III > II > I (D) I > III > II

Q.9 The incorrect statement among the following is: [JEE 1997]
(A) the first ionisation potential ofAl is less than the first ionisation potential of Mg
(B) the second ionisation potential of Mg is greater than the second ionisation potential of Na
(C) the first ionisation potential of Na is less than the first ionisation potential of Mg
(D) the third ionisation potential of Mg is greater than the third ionisation potential ofAl

Q.10 Which of the following are amphoteric? [REE 1997]

(A) Be(OH)2 (B) Sr(OH)2 (C) Ca(OH)2 (D)Al(OH)3

Q.11 Li+, Mg2+, K+,Al3+ (Arrange in increasing order of radii) [JEE 1997]

Q.12 Which one of the following statement (s) is (are) correct? [JEE 1998]
5 1
(A) The electronic configuration of Cr is [Ar] 3d 4s .(Atomic No. of Cr = 24)
(B) The magnetic quantum number may have a negative value
(C) In silver atom, 23 electrons have a spin of one type and 24 of the opposite type.(At. No. of Ag = 47)
(D) The oxidation state of nitrogen in HN3 is –3.

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Question No. 13 and 14

In following question a Statement 1 and Statement 2 is given. Choose the correct answers from the
codes A, B, C, D given for given question.
(A) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.
(B) Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for
statement-1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true.
Q.13 Statement-1: F atom has a less negative electron gain enthalpy than Cl atom. [JEE 2000]
Statement-2: Additional electron is repelled more efficiently by 3p electron in Cl atom than by 2p
electron in F atom.

Q.14 Statement-1: Al(OH)3 is amphoteric in nature. [JEE 2000]

Statement-2: Al –O and O – H bonds can be broken with equal ease in Al(OH)3.

Q.15 The correct order of radii is: [JEE 2000]

(A) N < Be < B (B) F– < O2– < N3– (C) Na < Li < K (D) Fe3+ < Fe2+ < Fe4+

Q.16 The correct order of acidic strength is: [JEE 2000]

(A) Cl2O7 > SO3 > P4O10 (B) CO2 > N2O5 > SO3
(C) Na2O > MgO > Al2O3 (D) K2O > CaO > MgO

Q.17 The IE1 of Be is greater than that of B. [T/F] [JEE 2001]

Q.18 The set representing correct order of IP1 is [JEE 2001]

(A) K > Na > Li (B) Be > Mg > Ca (C) B > C > N (D) Fe > Si > C

Q.19 Identify the least stable ion amongst the following: [JEE 2002]
(A) Li– (B) Be– (C) B– (D) C –

Q.20 Identify the correct order of acidic strengths of CO2, CuO, CaO, H2O: [JEE 2002]
(A) CaO < CuO < H2O < CO2 (B) H2O < CuO < CaO < CO2
(C) CaO < H2O < CuO < CO2 (D) H2O < CO2 < CaO < CuO

Q.21 In an atom, the total number of electrons having quantum numbers n = 4, | ml | = 1 and
1
ms = – is [JEEAdvance 2014]
2

Q.22 Not considering the electronic spin, the degeneracy of the second excited state (n = 3) of H atom is 9,
while the degeneracy of the second excited state of H– is : [JEE Advance 2015]

Q.23 The increasing order of atomic radii of the following Group-13 elements is [JEEAdvance 2016]
(A) Al < Ga < In < Tl (B) Ga < Al < In < Tl (C) Al < In < Ga < Tl (D) Al < Ga < Tl < In

Q.24 The option(s) with only amphoteric oxide is(are) [JEEAdvance 2017]
(A) Cr2O3, BeO, SnO, SnO2 (B) Cr2O3, CrO, SnO, PbO
(C) ZnO, Al2O3, PbO, PbO2 (D) NO, B2O3, PbO, SnO2

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EXERCISE-4
(NCERT Exampler)

Multiple choice question (Type-I)

Q.1 Consider the isoelectronic species, Na+, Mg2+, F¯ and O2–. The correct order of increasing length of
their radii is _________.
(A) F¯ < O2– < Mg2+ < Na+ (B) Mg2+ < Na+ < F¯ < O2–
(C) O2– < F¯ < Na+ < Mg2+ (D) O2– < F¯ < Mg2+ < Na+

Q.2 Which of the following is not an actinoid?

(A) Curium (Z = 96) (B) Californium (Z = 98)
(C) Uranium (Z = 92) (D) Terbium (Z = 65)

Q.3 The order of screening effect of electrons of s, p, d and f orbitals of a given shell of an atom on its outer
shell electrons is:
(A) s > p > d > f (B) f > d > p > s (C) p < d < s > f (D) f > p > s > d

Q.4 The first ionisation enthalpies of Na, Mg,Al and Si are in the order:
(A) Na < Mg > Al < Si (B) Na > Mg > Al > Si
(C) Na < Mg < Al < Si (D) Na > Mg > Al < Si

Q.5 The electronic configuration of gadolinium (Atomic number 64) is

(A) [Xe] 4f3 5d5 6s2 (B) [Xe] 4f7 5d2 6s1
7 1
(C) [Xe] 4f 5d 6s 2 (D) [Xe] 4f8 5d6 6s2

Q.6 The statement that is not correct for periodic classification of elements is:
(A) The properties of elements are periodic function of their atomic numbers.
(B) Non metallic elements are less in number than metallic elements.
(C) For transition elements, the 3d-orbitals are filled with electrons after 3p-orbitals and before
4s-orbitals.
(D) The first ionisation enthalpies of elements generallyincrease with increase in atomic number as we go
along a period.

Q.7 Among halogens, the correct order of amount of energyreleased in electron gain (electron gain enthalpy)
is:
(A) F > Cl > Br > I (B) F < Cl < Br < I
(C) F < Cl > Br > I (D) F < Cl < Br < I

Q.8 The period number in the long form of the periodic table is equal to
(A) magnetic quantum number of any element of the period.
(B) atomic number of any element of the period.
(C) maximum Principal quantum number of any element of the period.
(D) maximumAzimuthal quantum number of anyelement of the period.

Q.9 The elements in which electrons are progressively filled in 4f-orbital are called
(A) actinoids (B) transition elements
(C) lanthanoids (D) halogens
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Q.10 Which of the following is the correct order of size of the given species:
(A) I > I¯ > I+ (B) I+ > I¯ > I (C) I > I+ > I¯ (D) I¯ > I > I+

Q.11 The formation of the oxide ion, O2– (g), from oxygen atom requires first an exothermic and then an
endothermic step as shown below:
O (g) + e¯  O¯ (g) ; H  = – 141 kJ mol–1
O¯ (g) + e¯  O2– (g); H  = + 780 kJ mol–1
Thus process of formation of O2– in gas phase is unfavourable even though O2– is isoelectronic with
neon. It is due to the fact that,
(A) oxygen is more electronegative.
(B) addition of electron in oxygen results in larger size of the ion.
(C) electron repulsion outweighs the stabilitygained by achieving noble gas configuration.
(D) O¯ ion has comparatively smaller size than oxygen atom.

Q.12 Comprehension given below is followed by some multiple choice questions. Each question has one
correct option. Choose the correct option. In the modern periodic table, elements are arranged in order
of increasing atomic numbers which is related to the electronic configuration. Depending upon the type
of orbitals receiving the last electron, the elements in the periodic table have been divided into four
blocks, viz, s, p, d and f. The modern periodic table consists of 7 periods and 18 groups. Each period
begins with the filling of a new energy shell. In accordance with theArfbau principle, the seven periods
(1 to 7) have 2, 8, 8, 18, 18, 32 and 32 elements respectively. The seventh period is still incomplete. To
avoid the periodic table being too long, the two series of f-block elements, called lanthanoids and actinoids
are placed at the bottom of the main body of the periodic table.
(a) The element with atomic number 57 belongs to
(A) s-block (B) p-block (C) d-block (D) f-block

(b) The last element of the p-block in 6th period is represented by the outermost electronic configuration.
(A) 7s2 7p6 (B) 5f14 6d10 7s2 7p0
(C) 4f14 5d10 6s2 6p6 (D) 4f14 5d10 6s2 6p4

(c) Which of the elements whose atomic numbers are given below, cannot be accommodated in the present
set up of the long form of the periodic table?
(A) 107 (B) 118 (C) 126 (D) 102

(d) The electronic configuration of the element which is just above the element with atomic number 43 in the
same group is ________.
(A) 1s2 2s2 2p6 3s2 3p6 3d5 4s2 (B) 1s2 2s2 2p6 3s2 3p6 3d5 4s3 4p6
(C) 1s2 2s2 2p6 3s2 3p6 3d6 4s2 (D) 1s2 2s2 2p6 3s2 3p6 3d7 4s2

(e) The elements with atomic numbers 35, 53 and 85 are all ________.
(A) noble gases (B) halogens (C) heavy metals (D) light metals

Q.13 Electronic configurations of four elementsA, B, C and D are given below :

(a) 1s2 2s2 2p6 (b) 1s2 2s2 2p4 (c) 1s2 2s2 2p6 3s1 (d) 1s2 2s2 2p5
Which of the following is the correct order of increasing tendency to gain electron :
(A) a < c < b < d (B) a < b < c < d (C) d < b < c < a (D) d < a < b < c

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 PERIODIC PROPERTIES

Multiple choice question (Type-II)

In the following questions two or more options may be correct.
Q.14 Which of the following elements can show covalency greater than 4?
(A) Be (B) P (C) S (D) B

Q.15 Those elements impart colour to the flame on heating in it, the atoms of which require low energy for the
ionisation (i.e., absorb energy in the visible region of spectrum). The elements of which of the following
groups will impart colour to the flame?
(A) 2 (B) 13 (C) 1 (D) 17

Q.16 Which of the following sequences contain atomic numbers of onlyrepresentative elements?
(A) 3, 33, 53, 87 (B) 2, 10, 22, 36 (C) 7, 17, 25, 37, 48 (D) 9, 35, 51, 88

Q.17 Which of the following elements will gain one electron more readily in comparison to other elements of
their group?
(A) S (g) (B) Na (g) (C) O (g) (D) Cl (g)

Q.18 Which of the following statements are correct?

(A) Helium has the highest first ionisation enthalpy in the periodic table.
(B) Chlorine has less negative electron gain enthalpy than fluorine.
(C) Mercury and bromine are liquids at room temperature.
(D) In any period, atomic radius of alkali metal is the highest.

Q.19 Which of the following sets contain onlyisoelectronic ions?

(A) Zn2+, Ca2+, Ga3+, Al3+ (B) K+, Ca2+, Sc3+, Cl¯
3– 2–
(C) P , S , Cl¯, K + (D) Ti 4+, Ar, Cr3+, V5+

Q.20 In which of the following options order of arrangement does not agree with the variation of property
indicated against it?
(A) Al3+ < Mg2+ < Na+ < F¯ (increasing ionic size)
(B) B < C < N < O (increasing first ionisation enthalpy)
(C) I < Br < Cl < F (increasing electron gain enthalpy)
(D) Li < Na < K < Rb (increasing metallic radius)

Q.21 Which of the following have no unit?

(A) Electronegativity (B) Electron gain enthalpy
(C) Ionisation enthalpy (D) Metallic character

Q.22 Ionic radii vary in

(A) inverse proportion to the effective nuclear charge.
(B) inverse proportion to the square of effective nuclear charge.
(C) direct proportion to the screening effect.
(D) direct proportion to the square of screening effect.

Q.23 An element belongs to 3rd period and group-13 of the periodic table. Which of the following properties
will be shown by the element?
(A) Good conductor of electricity (B) Liquid, metallic
(C) Solid, metallic (D) Solid, non metallic
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Short Answer type

Q.24 Explain why the electron gain enthalpy of fluorine is less negative than that of chlorine.

Q.25 All transition elements are d-block elements, but all d-block elements are not transition elements. Explain.

Q.26 Identify the group and valency of the element having atomic number 119. Also predict the outermost
electronic configuration and write the general formula of its oxide.

Q.27 Ionisation enthalpies of elements of second period are given below :

Ionisation enthalpy/ k cal mol–1 : 520, 899, 801, 1086, 1402, 1314, 1681, 2080.
Match the correct enthalpy with the elements and complete the graph given in Figure.Also write symbols
of elements with their atomic number.
2500
Ionisation enthalpy
–1

2000
rH/kJ mol

1500

1000

500
1 2 3 4 5 6 7 8 9
Atomic number of elements

Q.28 Among the elements B,Al, C and Si,

(i) which element has the highest first ionisation enthalpy?
(ii) which element has the most metallic character?
Justify your answer in each case.

Q.29 Write four characteristic properties of p-block elements.

Q.30 Choose the correct order of atomic radii of fluorine and neon (in pm) out of the options given below and
justify your answer.
(i) 72, 160 (ii) 160, 160 (iii) 72, 72 (iv) 160, 72

Q.31 Illustrate by taking examples of transition elements and non-transition elements that oxidation states of
elements are largely based on electronic configuration.

Q.32 Nitrogen has positive electron gain enthalpy whereas oxygen has negative. However, oxygen has lower
ionisation enthalpythan nitrogen. Explain.

Q.33 First member of each group of representative elements (i.e., s and p-block elements) shows anomalous
behaviour. Illustrate with two examples.

Q.34 p-Block elements form acidic, basic and amphoteric oxides. Explain each propertybygiving two examples
and also write the reactions of these oxides with water.

Q.35 How would you explain the fact that first ionisation enthalpy of sodium is lower than that of magnesium
but its second ionisation enthalpy is higher than that of magnesium?
Q.36 What do you understand by exothermic reaction and endothermic reaction? Give one example of each
type.
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Q.37 Arrange the elements N, P, O and S in the order of-

(i) increasing first ionisation enthalpy. (ii) increasing non metallic character.
Give reason for the arrangement assigned.

Q.38 Explain the deviation in ionisation enthalpy of some elements from the general trend by using figure
2500
Ionisation enthalpy (2080) Ne
–1
rH/kJ mol 2000
(1681) F

1500 (1402) N

O (1314)
1000 (899) Be C (1086)

(520) Li B (801)
500
1 2 3 4 5 6 7 8 9 10
Atomic number of elements

Q.39 Explain thefollowing:

(a) Electronegativity of elements increase on moving from left to right in the periodic table.
(b) Ionisation enthalpy decrease in a group from top to bottom?

Q.40 How does the metallic and non metallic character vary on moving from left to right in a period?

Q.41 The radius of Na+ cation is less than that of Na atom. Give reason.

Q.42 Among alkali metals which element do you expect to be least electronegative and why?

Matching Type
Q.43 Match the correct atomic radius with the element.
Element Atomic radius (pm)
Be 74
C 88
O 111
B 77
N 66
Q.44 Match the correct ionisation enthalpies and electron gain enthalpies of the following elements.
Elements H 1 H 2  eg H
(i) Most reactive non metal A. 419 3051 – 48
(ii) Most reactive metal B. 1681 3374 – 328
(iii) Least reactive element C. 738 1451 – 40
(iv) Metal forming binaryhalide D. 2372 5251 + 48

Q.45 Electronic configuration of some elements is given in Column I and their electron gain enthalpies are
given in Column II. Match the electronic configuration with electron gain enthalpy.
Column (I) Column (II)
Electronic configuration Electron gain enthalpy/kJ mol–1
(i) 1s2 2s2 sp6 (A) – 53
2 2
(ii) 1s 2s 2p 3s6 1 (B) – 328
(iii) 1s2 2s2 2p5 (C) – 141
2
(iv) 1s 2s 2p2 4 (D) + 48

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Assertion and Reason Type

In the following questions a statement of Assertion (A) followed by a statement of Reason (R)
is given. Choose the correct option out of the choices given below each question.
Q.46 Assertion (A) : Generally, ionisation enthalpy increases from left to right in a period.
Reason (R) : When successive electrons are added to the orbitals in the same principal quantum level,
the shielding effect of inner core of electrons does not increase verymuch to compensate
for the increased attraction of the electron to the nucleus.
(A)Assertion is correct statement and reason is wrong statement.
(B)Assertion and reason both are correct statements and reason is correct explanation of assertion.
(C)Assertion and reason both are wrong statements.
(D)Assertion is wrong statement and reason is correct statement.

Q.47 Assertion (A) : Boron has a smaller first ionisation enthalpy than beryllium.
Reason (R) : The penetration of a 2s electron to the nucleus is more than the 2p electron hence 2p
electron is more shielded by the inner core of electrons than the 2s electrons.
(A)Assertion and reason both are correct statements but reason is not correct explanation for assertion.
(B)Assertion is correct statement but reason is wrong statement.
(C)Assertion and reason both are correct statements and reason is correct explanation for assertion.
(D)Assertion and reason both are wrong statements.

Q.48 Assertion (A) :Electron gain enthalpy becomes less negative as we go down a group.
Reason (R) : Size of the atom increases on going down the group and the added electron would be
farther from the nucleus.
(A)Assertion and reason both are correct statements but reason is not correct explanation for assertion.
(B)Assertion and reason both are correct statements and reason is correct explanation for assertion.
(C)Assertion and reason both are wrong statements.
(D)Assertion is wrong statement but reason is correct statement.

Long Answer type

Q.49 Discuss the factors affecting electron gain enthalpy and the trend in its variation in the periodic table.

Q.50 Define ionisation enthalpy. Discuss the factors affecting ionisation enthalpy of the elements and its trends
in the periodic table.

Q.51 Justify the given statement with suitable examples— “the Properties of the elements are a periodic
function of their atomic numbers”.

Q.52 Write down the outermost electronic configuration of alkali metals. How will you justifytheir placement
in group 1 of the periodic table?

Q.53 Write the drawbacks in Mendeleev’s periodic table that led to its modification.

Q.54 In what manner is the long form of periodic table better than Mendeleev’s periodic table? Explain with
examples.

Q.55 Discuss and compare the trend in ionisation enthalpy of the elements of group1 with those of group17
elements.

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ANSWER KEY

EXERCISE-1
Q.1 C Q.2 B Q.3 C Q.4 D Q.5 B Q.6 C Q.7 B

Q.8 C Q.9 C Q.10 A Q.11 C Q.12 C Q.13 B Q.14 C

Q.15 D Q.16 C Q.17 C Q.18 C Q.19 B Q.20 C Q.21 A

Q.22 B Q.23 D Q.24 C Q.25 B Q.26 D Q.27 C Q.28 D

Q.29 A Q.30 A Q.31 C Q.32 D Q.33 C Q.34 D Q.35 C

Q.36 B Q.37 B Q.38 D Q.39 D Q.40 C Q.41 C Q.42 C

Q.43 B Q.44 C Q.45 A Q.46 D Q.47 C Q.48 B Q.49 D

Q.50 D Q.51 A Q.52 B Q.53 B Q.54 C Q.55 C Q.56 C

Q.57 B Q.58 B Q.59 C Q.60 A Q.61 D Q.62 A Q.63 C

Q.64 B Q.65 C Q.66 C Q.67 D Q.68 A Q.69 C Q.70 D

Q.71 C Q.72 A Q.73 B Q.74 B Q.75 C Q.76 D Q.77 B

Q.78 B Q.79 C Q.80 A Q.81 C Q.82 B Q.83 A Q.84 C

Q.85 A Q.86 A Q.87 D Q.88 D Q.89 A Q.90 C Q.91 A

Q.92 A Q.93 A Q.94 D Q.95 A Q.96 D Q.97 A Q.98 D

Q.99 D Q.100 A Q.101 A Q.102 B Q.103 C Q.104 C Q.105 B

Q.106 C Q.107 A Q.108 C Q.109 D Q.110 C Q.111 B Q.112 C

Q.113 C Q.114 A Q.115 D Q.116 A Q.117 D Q.118 A Q.119 C

Q.120 C Q.121 C Q.122 D Q.123 B Q.124 B Q.125 A Q.126 D

Q.127 D Q.128 C Q.129 C Q.130 D Q.131 B Q.132 B Q.133 B

Q.134 D Q.135 C Q.136 A Q.137 D Q.138 D Q.139 B Q.140 A

Q.141 C Q.142 B Q.143 A Q.144 A Q.145 B Q.146 A Q.147 B

Q.148 D Q.149 A Q.150 A Q.151 A Q.152 D Q.153 C Q.154 C

Q.155 B Q.156 B Q.157 A Q.158 A Q.159 D Q.160 D Q.161 A

Q.162 D Q.163 B Q.164 B Q.165 D Q.166 C Q.167 D Q.168 D

Q.169 A Q.170 B Q.171 C Q.172 C Q.173 A Q.174 A Q.175 D

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 PERIODIC PROPERTIES

Q.176 C Q.177 B Q.178 C Q.179 A Q.180 C Q.181 B Q.182 A

Q.183 A Q.184 A Q.185 D Q.186 B Q.187 A Q.188 A Q.189 B

Q.190 B Q.191 B Q.192 C Q.193 B Q.194 A Q.195 C Q.196 B

Q.197 D Q.198 C Q.199 C Q.200 B Q.201 A Q.202 A Q.203 C

Q.204 B Q.205 C Q.206 B Q.207 D Q.208 B Q.209 D Q.210 C

Q.211 C Q.212 B Q.213 C Q.214 D Q.215 B Q.216 B Q.217 C

Q.218 A Q.219 C Q.220 B Q.221 B Q.222 B Q.223 C Q.224 B

Q.225 B Q.226 A Q.227 C Q.228 B Q.229 B Q.230 B Q.231 D

Q.232 C Q.233 A Q.234 B Q.235 A Q.236 B Q.237 C Q.238 C

Q.239 B Q.240 D Q.241 B Q.242 C Q.243 C Q.244 A Q.245 B

Q.246 C Q.247 D Q.248 C Q.249 C Q.250 C Q.251 B Q.252 C

Q.253 D Q.254 D Q.255 D Q.256 C Q.257 C Q.258 B Q.259 B

Q.260 D Q.261 B Q.262 D Q.263 D Q.264 C Q.265 B Q.266 B

Q.267 C Q.268 A Q.269 D Q.270 B Q.271 B Q.272 A Q.273 B

Q.274 A Q.275 A Q.276 D Q.277 D Q.278 D Q.279 A Q.280 D

Q.281 B Q.282 C Q.283 D Q.284 B Q.285 C Q.286 A Q.287 B

Q.288 A Q.289 D Q.290 C Q.291 B

EXERCISE-2
Q.1 BCD Q.2 ABC Q.3 ACD Q.4 BCD Q.5 ACD

Q.6 ABC Q.7 ABD Q.8 AD Q.9 BC Q.10 ABCD

Q.11 ABD Q.12 ABC Q.13 ABCD Q.14 BCD Q.15 BC

Q.16 AC Q.17 AC Q.18 AD Q.19 ACD Q.20 AD

Q.21 BC Q.22 CD Q.23 CD Q.24 AC Q.25 ABD

Q.26 CD Q.27 ABC Q.28 AC Q.29 ACD Q.30 ABCD

Q.31 ABD Q.32 ABCD Q.33 ACD Q.34 ABC Q.35 ABC

Q.36 ABD Q.37 ABC Q.38 ABCD Q.39 AD Q.40 ABCD

Q.41 BCD Q.42 ABC Q.43 BCD Q.44 ABD Q.45 ABC

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Q.46 BC Q.47 ABCD Q.48 BC Q.49 ABC Q.50 ABC

Q.51 ABC Q.52 ABD Q.53 BC Q.54 ABCD Q.55 ABC

Q.56 ABC Q.57 ABCD Q.58 AB Q.59 AC Q.60 ABC

Q.61 ABCD Q.62 AC Q.63 ABCD Q.64 AB Q.65 AB

Q.66 ABCD Q.67 ABCD Q.68 AD Q.69 ABC Q.70 BD

Q.71 ACD Q.72 AC Q.73 BD Q.74 ABC Q.75 AC

Q.76 AD Q.77 ABD Q.78 CD Q.79 ABD Q.80 BCD

Q.81 AC Q.82 AC Q.83 BCD Q.84 ABC Q.85 C

Q.86 B Q.87 A Q.88 A Q.89 C Q.90 C

Q.91 A Q.92 A Q.93 D Q.94 C Q.95 A

Q.96 B Q.97 B Q.98 B Q.99 C Q.100 B

Q.101 D Q.102 B Q.103 C Q.104 B Q.105 A

Q.106 C Q.107 A Q.108 D Q.109 B Q.110 B

Q.111 B Q.112 A Q.113 D Q.114 A Q.115 B

Q.116 C Q.117 A Q.118 A Q.119 A Q.120 C

Q.121 B Q.122 D Q.123 C Q.124 B Q.125 C

Q.126 C Q.127 C Q.128 A Q.129 B Q.130 A

Q.131 (A) R; (B) S; (C) Q ; (D) P Q.132 (A) P,Q,R (B) R,S (C) Q,R (D) P,Q

Q.133 (A) P,R,S (B) P,S (C) Q,S (D) P,Q,R,S Q.134 (A) P,R ; (B) R,S ; (C) P,Q,R

Q.135 (A) P,S,T (B) Q,R (C) Q,R (D) S,T Q.136 (A) P,Q,R (B) S (C) Q,R

Q.137 (A) P, Q (B) P, S (C) P, R Q.138 (A) Q, T (B) P,R, (C) P,R,S (D) T

Q.139 (A) P,Q, (B) PT (C) Q,R,S (D) Q,R,T Q.140 (A) P,Q (B) R (C) S

Q.141 (A) P, Q, T; (B) S, T; (C) P, R, T ; (D) P, Q, R, T

Q.142 (A) QT (B) PQR (C) R (D) RS Q.143 D

Q.144 (A) QS (B) PRST (C) QT (D) PRT Q.145 (A) PS (B) PQRS (C) PQR

Q.146 (A) PR (B) QS (C) PST (D) PR Q.147 + 4

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Q.148 4
Ni  1s2 2s22p6 3s23p6 3d84s2

2 8 8 8 2
(1s) ( 2s2p) ( 3s3p) (3d) (4s)
Grouping 
(n–3) (n–2) (n–1) n
= 10 × 1 + 16 × 0.85 + 1 × 0.35 = 23.95

Zeff = Z –  = 28–23.95 = 4.05 ~

 4

Q.149 6

X = EN(B) – EN(A) = 3.5 – 2.0 = 1.5

% Ionic character = 16X + 3.5 (X)2
 exp
% Ionic character = 100
 theo

1
 exp   10  29
3  100
16(1.5) + 3.5 (1.5)2 =
1.6  10  3.92  10 10
19

µexp = 5.99 approximate 6

Q.150 125
Possible subshells are present in 9th period
9s 8d 7f 6g 9p
Total electron 5 + 25 + 35 + 45 + 15 = 125 Ans.

Q.151 3
3d )1
(1s) 2 (2s 2p)8 (3s 3p)8 ( 4s) 2
(

18 1 nd 0.00

0 × 0.35
 = 18 + 0.00 = 18.00

Zeff =Z–S

= 21 – 18  3 Ans.

Q.152 2
Cd & Hg are d-block element but not transitional

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Q.153 3.06
I(g)  I– (g)
Ereleased = 4.9 × 10–13 J for one million atoms.

4.9 1013
For one atom, Energy released =
106
= 4.9 × 10–3 × 10–6 = 4.9 × 10–19 Joule

4.9 1019
Ereleased = eV/atm = 3.606 eV / atom.
1.6 1019
Ans. (1 eV = 1.6 × 10–19 Joule)

Q.154 3.22 eV

Electronegativity of F – Electronegativity of Cl = 0.208 61  38  58

4eV – Electronegativity of Cl = 0.779 eV
Electronegativity of Cl = (4 – 0.779) eV = 3.22 eV Ans

Q.155 3

Q.156 3
2 2 6 2 6 10 2 4p6) (4d) , (5s2)
39Y : (1s ) (2s 2p ) (3s 3p ) (3d ) (4s
39th electron of Y is present in 4d-subshell
Zeff =Z–
= 39 – 
4d = 36 × 1 + 0 × 0.35  36
 Zeff = 3 Ans.

Q.157 2
For 2.84 B.M., 2 unpaired electron required.
Fe+2 [Ar] 3d5
Cr [Ar] 3d5·4s1
Cr+3 [Ar] 3d3
Ti+2 [Ar] 3d2
Mn +2 [Ar] 3d5
V+3 [Ar] 3d2

Q.158 44
Hg+2 Hg  z = 80

3d10 

4d10 
Low shielding shown by  d or f electron  4d14 5d  involved orbitals total electron = 44
10

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Q.159 3
83 79 42 64 37 54 34
      
p-block d d f s p p
Total p-block element = 0003

Q.160 2
Each orbital contained maximum 2e¯

Q.161 2

Q.162 8
25Mn  1s2
2s2 2p6
3s2 3p6 3d5
4s2
Electrons in s-subshell = 8
Q.163 1085
PS
 increases by .35
so, 10.5 + .35
 = 10.85 Ans

Q.164 1573
dAB = rA + rB – 0.09 (xA – xB) Å
= 1.2 + 0.4 – 0.09 (2.4 – 2.1)
= 1.6 – 0.027 Å = 1.573 Å
dAB × 1000 = x = 1573 Ans.

Q.165 5
(i) 2Cl(g)  Cl2(g) (ii) Na+(g) + F(g) + e–  NaF(s)
(iii) Cl(g) + H2O + e–  Cl–(aq) (iv) Al+2(g) + e–  Al+1(g)
(v) P(g) + e–  P–(g)

Q.166 140 Å

dBF = rF + rB – 0.09 | ( X F  X B |

= 0.85 + 0.73 – 0.09 × 2 = 1.40

In triangleADC
AC
cos 30° =
AD

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3 AC

2 1.40
3 1.40
 AC
2
dF–F = 2AC = 3  1.40
100  3  1.40
= 140 Å Ans.
2

Q.167 46
Target Reaction A+  A+4 (g) H = ax
A+2 + e–  A+(g) ....(1)
A (g)  A (g) + e ....(2)
+2 +3 –

A+4 (g) + e–  A+3 (g) ....(3)

__________________
From (2) – (1) – (3) A+(g)  A+4
––––––––––––––––––
8x + 23 x + 15 x = ax
46 x = ax
a = 46 Ans.

Q.168 89
S.No. Order Parameter Code Number
1. Na < Cl < F Electronegativity 28 
2. Be < Mg < Na Metallic character 53 
3. Al3+ > Mg Ionic radius 14
4. O < F < Cl | HEG| 8 
5. Cl2O7 > Al2O3 > Na2O Basic nature of oxide 59
28 + 53 + 8 = 0089

Q.169 193
O–  O + 1e–
S–  S + 1e–
EA (S) > EA (O)
IE1 (S–) > IE1 (O¯)
Atomic size Si > Cl
Number of unpaired electron Mn < Cr
58 + 22 + 113 = 193

Q.170 1929
N
n = 4, Min. = 19 [1s22s22p63s23p64s1]
Max. = 29 [1s22s22p63s23p64s13d10]  1929 Ans

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Q.171 625
Refer Slater's rule

Q.172 17
In V period
Atomic no. ofAlkali metal = 37 (Rb)
and Atomic no. of xenon = 54
 Diffn = 54 – 37 = 17 Ans.

Q.173 240
A 2+ (g)  A –(g), H = – 320 K
 IE 2  eg H1
A2+(g) IE1   A(g)   A
–

x + 3x + 12x = 320
16x = 320
x = 20

Q.174 5, Check the ions containing paired electrons (Write electronic configuration)

Q.175 14
(i) 1s2 2s2 2p3  N x=3
(ii) 1s2 2s2 2p6 3s2 4s2 3d8 y=2

(iii) 1s2 2s2 2p6 3s2 3p6 4s1 3d5

min. = 9, max. = 15 z=9

x + y + z = 14

Q.176 36, Percent ionic character = 18 (3.48 – 1.84)1.4

= 18 × 2 = 36%

Q.177 150
rm = 1.2 rc
180
 rc  rc = 150 ppm
1 .2

Q.178 5, NaCl, KF, RbCl, NaBr, KCl

Q.179 5072
9th period : 9s 6g 7f 8d 9p
2 18 14 10 6 = 50

10th period : 10s 6h 7g 8f 9d 10p

2 22 18 14 10 6 = 72
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Q.180 2, Large jump after 2nd I.E. so valency electron = 2, so group number = 2

Q.181 2
Fe+2 [Ar] 3d5
Cr [Ar] 3d5·4s1
Cr+3 [Ar] 3d3
Ti+2 [Ar] 3d2
Mn+2 [Ar] 3d5
V+3 [Ar] 3d2

Q.182 3

Q.183 5
IE of Li < Be > B
C<N>O
Si < P > S
Al < Ga > In
Na < Mg > Al

Q.184 112 , 'Uub' is Ununbium = 112

Q.185 4
µ = 4.9 B.M.
µ= n (n  2)
n = number of unpaired electron
=4

Q.186 5, SiO2, Cl2O7, CO2, B2O3, SO3 are acidic oxidic

Q.187 4 Q.188 3

Q.189 5, SiO2, Cl2O7, CO2, B2O3, SO3 are acidic oxidic

Q.190 7

Q.191 0
Zeff = Z – 
for Na, K, Rb, Cs, Zeff = 2.2
Thus Zeff of Na – Zeff of K = 0

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EXERCISE-3

SECTION-A

Q.1 A Q.2 B Q.3 B Q.4 B Q.5 A Q.6 A Q.7 C

Q.8 A Q.9 D Q.10 A Q.11 B Q.12 A Q.13 C Q.14 D

Q.15 C Q.16 C Q.17 B Q.18 D Q.19 A Q.20 A Q.21 A

Q.22 B Q.23 A Q.24 A Q.25 D

SECTION-B

Q.1 A Q.2 C Q.3 C Q.4 A Q.5 D Q.6 A Q.7 D

Q.8 A Q.9 B Q.10 AD Q.11 Al+3 < Mg2+ < Li+ < K+ Q.12 ABC Q.13 C

Q.14 C Q.15 B Q.16 A Q.17 True Q.18 B Q.19 B Q.20 A

Q.21 6 Q.22 3 Q.23 B Q.24 AC

EXERCISE-4

Q.1 B Q.2 D Q.3 A Q.4 A Q.5 C Q.6 C Q.7 C

Q.8 C Q.9 C Q.10 D Q.11 C

Q.12 (a) C (b) C (c) C (d) A (e) B

Q.13 A Q.14 BC Q.15 AC Q.16 AD Q.17 AD Q.18 ACD Q.19 BC

Q.20 BC Q.21 AD Q.22 AC Q.23 AC

Q.24 The added electron in fluorine goes to second quantum level. Due to small size of fluorine it experiences

repulsion from other electrons much more in comparison to that in chlorine because in chlorine, the

electron is added to 3rd quantum level in which larger space is available for movement.

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Q.26 Group : 1, Valency : 1

Outermost electronic configuration = 8s1

Formula of Oxide = M2O

Q.27 Compare your plot with the plot given in the textbook.

Q.28 (i) Carbon (ii)Aluminium Q.30 (i)

Q.32 The outermost electronic configuraton of nitrogen ( 2s 2 2p1x 2p1y 2p1z ) is very stable because p-orbital is

half filled.Addition of extra electron to any of the 2p orbital requires energy.

Oxygen has 4 electrons in 2p orbitals and acquires stable configuration i.e., 2p3 configuration after

removing one electron.

Q.35 After removing 1 electron from the sodium atom the ion formed acquires the configuration of inert gas,

neon. The second electron is removed from one of the 2p-orbitals which are completely filled i.e., have

a total of 6 electrons and are closer to the nucleus.

Q.37 (i) S < P < N < O

(ii) P < S < N < O

Q.39 (a) Decrease in size of atom and increase in nuclear charge.

(b) Increase in atomic size.

Q.40 Metallic character decreases and non metallic character increases in moving from left to right in a period.

It is due to increase in ionisation enthalpy and electron gain enthalpy.

Q.41 Decrease of one shell.

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Q.42 Electronegativity decreases in a group from top to bottom. Thus, caesium is the least electronegative

element.

Q.43 Be = 111, O = 66, C = 77, B = 88, N = 74

Q.44 Most reactive non metal = B, Most reactive metal = A,

Least reactive element = D, Metal forming binary halide = C

Q.45 (i)  (D); (ii)  (A) (iii)  (B) (iv)  (C)

Q.46 C Q.47 C Q.48 D

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