DPP-Periodic Table - Combined
DPP-Periodic Table - Combined
9.     The IUPAC name of the element which is placed just after 105Db is the periodic table, will be :-
       (A) Unnilpentium
       (B) Ununnilium
       (C) Unnilhexium
       (D) Unnilquadium
10.    The element that was present in Ascending position in Lothar – Meyer curve is ..................
       (A) Cl
       (B) Ca
       (C) Si
       (D) Mn
11.    Atomic weight of an element ‘X’ is 32 and that of element Z is 127. At wt. of their intermediate element
       Y, as per Dobereiner triad will be :
       (A) 171
       (B) 32
       (C) 79.5
       (D) 85.5
Answer Key
  Question      1     2     3   4   5   6    7       8   9   10   11   12   13   14   15
  Answer        C     C     D   A   D   B    A       B   C   A    C    C    A    C    C
                                                   Solutions DPP-01
1.     Ans. C
       Be, Mg, Ca obeys Newland's octave rule.
2.     Ans. C
       Dobereiner triad is followed by -
       (a) P, As, Sb              (d) S, Se, Te
3.     Ans. D
       In option (D) Al and Si is not anomalous pair of elements in the Mendeleev's periodic table.
       Atomic mass of Si > Atomic mass of Al
4.     Ans. A
       Eka silicon – Ge
       Eka aluminium – Ga
       Eka manganese – Tc
       Eka Boron - Sc
5.     Ans. D
       Representative elements are elements of s and p-block
       Atomic No.         Electronic configuration
       9                  [He] 2s2 3p5
                                        10
       31                 [Ar] 4s2 3d        4p1
       53                 [Kr] 5s24 d 5p5
                                   10
                                    10       14
       83                 [Xe] 6s25 d 4f 6p2
6.     Ans. B
       → Number of valence shell electrons are same in groups.
       → IIIrd B groups contains 4 transition, 14 Lanthanides & 14 actinides
7.     Ans. A
       ns𝟐 np𝟔 → 18th group elements general configuration.
8.     Ans. B
       These elements are Lanthanides which are placed in 6th period and III B group.
9.     Ans. C
       106 → Unnilhexium
10.    Ans. A
       Halogens occupy Ascending positions in Lothar – Meyer curve.
11.    Ans. C
       X    Y    Z
       32 A     127
            32 + 137 159
       A=           =    = 79.5
               2      2
12.    Ans. C
       Alkali metals occupy top positions at Lothar Meyer curve.
13.    Ans. A
       Li and Mg show diagonal relationship
14.    Ans. C
       Zn, Cd, Hg is not transition elements.
15.    Ans. C
       Lanthanoids belong to III group and VI period.
11.    What is the value of effective nuclear charge for last electron of yttrium (Y) ?
       (A) 36
       (B) 3
       (C) 39
       (D) 9
13.    Find the shielding constant () by the first electron enter in H- ?
       (A) .70
       (B) 1
       (C) .35
       (D) .30
14. Maximum Number of electrons in sulphur which has same value of 𝐙𝐞𝐟𝐟
Answer Key
     Question      1        2   3   4   5     6     7    8   9   10   11   12   13   14
     Answer        D        C   C   D   C     D     B    A   C   D    B    A    D    B
                                                 Solutions DPP-02
1.     Ans. D
       Effective nuclear change in a group first increases then remains constant.
2. Ans. C
3.     Ans. C
     Correct order of penetration power is:
       ns > np > nd > nf
4.     Ans. D
       H, He+ , Li+2 all are single electron species. So, there is no other electron available for shielding. That's why
       screening effect is not observed in all of these.
5.     Ans. C
       M = (1s 2 ) (2s 2 2p3 )
            Zeff = Z – σ
       = 7 – (2 × 0.85 + 4 × 0.35)
       = 7 – (3.1)
       = 3.9
6.     Ans. D
       We know from Left to right in periodic table Z (atomic no.) increase by 1, σ increase by 0.35.
       So, Zeff = Z – σ increase by 0.65 (applicable only for s & p block)
       Li              Be            B
B  x + 1.3
7.     Ans. B
                  Z
       Zeff ∝
             e
       For M, M+, M– value of Z (Atomic number) remains same.
       So, on increasing Number of electrons, Zeff decreases
       M+ > M > M –
8.     Ans. A
                 Z
       Zeff ∝
                 e
        Given series is isoelectronic series.
       So, No. of electron is same, but atomic number (Z) is different.
       So, Zeff ∝ Z
9.     Ans. C
       Cr = 1s 2 2s 2 2p6 3s 2 3p6 4s1 3d5
       Cr +3 = 1s 2 2s 2 2p6 3s 2 3p6 3d3
       (1s 2 ) (2s 2 2p6 ) (3s 2 3p6 ) (3d3 )
       σ = 1 × 2 + 0.85 × 8 + 0.35 × 10
       σ = 12.3
10.    Ans. D
       Electronic configuration of 30Zn : 1s2 2s2 2p6 3s2 3p6 4s2 3d10
       Slater configuration : (1s2) (2s2 2p6) (3s2 3p6) (3d10) (4s2)
        = (1 × 0.35) + (18 × 0.85) + (10 × 1) = 25.65
       zeff = z – 
       = 30 – 25.65 = 4.35
11.    Ans. B
       Electronic configuration of 30Zn : 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d1
       Slater configuration : (1s2) (2s2 2p6) (3s2 3p6) (3d10) (4s2 4p6) (4d1) (5s2)
        = (1 × 36) = 36
       zeff = z – 
       = 39 – 36 = 3
12.    Ans. A
       Subshell closest to nucleus will apply maximum screening effect.
13.    Ans. D
       H = 1s1
       H- = 1s1
        = 0.30 X 1 = 0.30
       Zeff = Z -  = 1 – 0.30 = 0.70
       Zeff = 0.70
       So  is = 0.30
       Ans. is (4)
14.    Ans. 8
       S → 1s 2 2s 2 2p6 3s 2 3p4
2.     Arrange the following in order of increasing atomic radii Na, Si, Al, Ar :-
       (A) Na < Si < Al < Ar
       (B) Si < Al < Na < Ar
       (C) Ar < Al < Si < Na
       (D) Na < Al < Si < Ar
3.     X-X bond length is 1.00Å and C-C bond length is 1.54Å. If electronegativities of X and C are 3.0 and 2.0
       respectively then C-X bond length is likely to be ?
       (A) 1.11
       (B) 2.1Å
       (C) 1.18Å
       (D) 2.4Å
5.     For the element X, student Mansi Measured its radius as 102 nm, student Rohit as 203 nm and Ankur as
       100 nm. Using same-apparatus. Their teacher explained that measurement were correct by saying that
       recorded value by three students were :-
       (A) crystal, vander wall's and covalent radii
       (B) Covalent, Crystal and vander wall's radii
       (C) Vander wall's, ionic and covalent radii
       (D) No is correct.
7.     In which of the following pair radius of second species is smaller than that of first specie.
       (A) Li, Na
       (B) Na+ , F –
       (C) N –3 , Al+3
       (D) Mn+7 , Mn+4
10.    Consider the isoelectronic series, 𝐊 + , 𝐒 𝟐− , 𝐂𝐥– 𝐚𝐧𝐝 𝐂𝐚+𝟐 , the radii of the ions decrease as :-
       (A)   Ca+2 > K + > Cl– > S –2
       (B)   Cl– > S 2− > K + > Ca+2
       (C)   S 2 – > Cl– > K + > Ca+2
       (D)   K + > Ca+2 > S 2− > Cl–
11.    Which of the following pair has approximately the same atomic radii ?
       (A) Zn and Hf
       (B) Al and Ga
       (C) (a) and (b) both
       (D) Al and Mg
12.    The covalent and Vander Waals radii of nitrogen respectively are :
       (A) 0.37 Å, 1.2Å
       (B) 0.37 Å, 3.7Å
       (C) 1.2 Å, 1.2Å
       (D) 1.2 Å, 0.37Å
15.    Choose the correct order of ionic radius for the following species :
       (A) Cl−  I −  Te2 −  Ar +
       (B) Te2 −  I −  Cl−  Ar +
       (C) I −  Te2−  Cl−  Ar +
       (D) I −  Cl−  Ar +  Te2 −
16.    The correct sequence which shows decreasing order of the ionic radii of the element is :
       (A) O2−  F−  Na+  Mg2+  Al3+
       (B) Al3+  Mg2+  Na+  F−  O2−
       (C) Na+  Mg2+  Al3+  O2−  F−
       (D) Na+  F−  Mg2+  O2−  Al3+
Answer Key
Question 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Answer C B C C A C C B B C C A A C B A D
                                                     Solutions DPP-03
1.     Ans. C
       F < N < P < Si
       Generally, Left to right in a period size decreases and down the group size increases.
2.     Ans. B
       Si < Al < Na < Ar (Due to Vander Waal radius)
3.     Ans. C
       rc +x = rc + rx – 0.09∆x             (Here x = difference in electronegativity i.e. 1)
          1.00 1.54
       =       +      – 0.09 (1)
            2     2
       = 1.27 – 0.09 = 1.18Å
       So, C-X bond length = 1.18 Å
4.     Ans. C
       Mg < Na < K < Rb
       Left to right in a period atomic radius decreases and top to bottom in a group atomic radius increases.
5.     Ans. A
       Covalent radii < Crystal radii < Vander waal's radi
6.     Ans. C
       Cs + ion has largest size due to large value of 'n'.
7.     Ans. C
       (i) Li < Na (n ↑ , atomic size ↑)
       (ii) Na+ < F – (Zeff For isoelectronic, Z ↑ , size ↓)
       (iii) N –3 > Al+3 (Zeff For isoelectronic, Z ↑ , size ↓)
                                      1
       (iv) Mn+7 < Mn+4 (size ∝           )
                                     Zeff
8.     Ans. B
                 1
       size ∝
                Zeff
       In option (B) correct order is
       F – > Na+ > Mg +2 (For isoelectronic, Z ↑ , size ↑ )
9.     Ans. B
                 1
       Size ∝        ∝ Number of shell
                Zeff
       (A) Li > Be < Mg
       (B) H + < Li+ < H –
       (C) Ne > O > F
       (D) O–2 > F – > Na+ (For iso electronic Z ↑, size ↓)
10.    Ans. C
       For isoelectronic species.
       Z ↑, size ↓
        S 2– > Cl– > K + > Ca+2
11.    Ans. C
       Zr and Hf same atomic radii due to lanthanide contraction.
       Al and Ga same atomic radii due to lanthanide contraction.
12.    Ans. A
       Covalent < Vander walls
         0.37 Å        1.2 Å
13.    Ans. A
       Cation has a smaller number of electrons than neutral atom. So, in cation Zeff is more hence, ionic radius of
       cation is always less than atomic radius.
14.    Ans. C
       Order of size (isoelectronic species)
          N-3        O-2        F-
         10e–        10e–      10e-
       Size order : F- < O-2 < N-3
15.    Ans. B
       For isoelectronic species
       Size order : Anion > Natural > Cation
16.    Ans. A
       For isoelectronic species.
       Size  Anion > Neutral > Cation
17.    Ans. D
                        1
       Ionic radii 
                       Z eff
8.     From the given set of species, point out the species from each set having least atomic radius :-
       (1) O2 ,F− ,Na+              (2) Ni, Cu, Zn     (3) Li, Be, Mg         (4) He, Li+, H-
       (A) O-2, Cu, Li, H-
       (B) Na+, Ni, Be, Li+
       (C) F-, Zn, Mg, He
       (D) Na+, Cu, Be, He
10.    Which of the following sequence is correct for decreasing order of ionic radius ?
       (A) Se-2, I-, Br-, O-2, F-
       (B) I-, Se-2, O-2, Br-, F-
       (C) Se-2, I-, Br-, F-, O-2
       (D) I-, Se-2, Br-, O-2, F-
14. Size of H– is smaller than how many elements among these: H, Li, Be, B, C, N, O, F, F –
Answer Key
     Question      1        2   3   4   5     6     7    8   9   10   11   12   13    14
     Answer        A        A   B   D   A     A     C    B   B   D    C    D    B,C   0
                                                             Solutions DPP-04
1.     Ans. A
       N–3       O–2          F–
                 S–2          Cl–
                              Br–
        size ∝ no. ofshell(n)
       So,
2. Ans. A
3.     Ans. B
       (i) Size of P3 < Q                  L → R in periodic table Zeff ↑ A. R. ↓
                       3p     3p1
       (ii) Size of R3 < S1                L → R in periodic table Zeff ↑ A. R. ↓
                        4p    4p
4.     Ans. D
                  1
       (size ∝          )
                 Zeff
       Ti+4 > Mn+7 ; K + < Cl– {For iso electronic ; σ is constant, so when Z increases then Z eff increases and size
       decreases.
       37 −
         Cl = 35 Cl– (e– & P are same)
                                     1
       P 3+ > P 5+ (size ∝                 ).
                                    Zeff
5.     Ans. A
       For iso electronic species
                   1
       (size ∝          )
                 Zeff
6.     Ans. A
       K2CrO4 = K+ + CrO−42
       CrO2 = Cr +2 + O2−2
       CrF3 = Cr +3 + F−
       CrCl3 = Cr +3 + Cl−
       As positive charge increases, ionic radius decreases.
7.     Ans. C
       Mn+7  Mn+5  Mn+2
8.     Ans. B
       (1) O2 ,F− ,Na+ → More Zeff, small size.
       (2) Ni, Cu, Zn → Ni has more Zeff, so small size.
       (3) Li, Be, Mg → Be has more Zeff, small size.
       (4) He, Li+, H– → Li+ has more Zeff, small size.
9.     Ans. B
       For Isoelectronic series, ionic radii depends on Z/e- value [where Z→ Atomic number and e- is number of
       electrons]
                              Z
       Higher the value of       smaller the ionic radii.
                              e−
10.    Ans. D
       No. of shells  Atomic Radius
       - ve charge  size
       I − Se−2  Br − O −2  F−
                               (No. of shells)
       5        4          2
11.    Ans. C
       Positive charge  Ionic Radius 
       So, Ans is Fe4 +  Fe3+  Fe2 +
12. Ans. D
14.    Ans. 0
       H– has greatest size among given species.
2.     (a) 𝐌(𝐠)
            –
                → 𝐌(𝐠)                    (b) 𝐌(𝐠) → 𝐌(𝐠)
                                                      +
                                                                 (c) 𝐌(𝐠)
                                                                      +      +𝟐
                                                                          → 𝐌(𝐠)       (d) 𝐌(𝐠)
                                                                                            +𝟐     +𝟑
                                                                                                → 𝐌(𝐠)
       Minimum and maximum Ionisation Potential would be of :-
       (A) a, d
       (B) b, c
       (C) c, d
       (D) d, a
4.     Successive ionisation energies of an element 'X' are given below (in kcal/mol)
       𝐈𝐏𝟏    𝐈𝐏𝟐     𝐈𝐏𝟑      𝐈𝐏𝟒
       165    195      556    595
       Electronic configuration of the element 'X' is:-
       (A)   1s 2 , 2s 2 2p6 , 3s 2 3p2
       (B)   1s 2 , 2s1
       (C)   1s 2 , 2s 2 2p2
       (D)   1s 2 , 2s 2 2p6 , 3s 2
5.     Out of 𝐍𝐚+ , 𝐌𝐠 +𝟐 , 𝐎–𝟐 𝐚𝐧𝐝 𝐍 –𝟑 , the pair of species showing minimum and maximum IP would be.
       (A)   Na+ , Mg +2
       (B)   Mg +2 , N –3
       (C)   N –3 , Mg +2
       (D)   O–2 , N –3
12.    The decreasing order of the ionization potential of the following elements is :
       (A) Ne >Cl > P > S > Al > Mg
       (B) Ne > Cl > P > S > Mg > Al
       (C) Ne > Cl > S > P > Mg > Al
       (D) Ne > Cl > S > P > Al > Mg
Answer Key
  Question      1     2     3   4   5   6   7        8   9   10   11   12   13    14     15
  Answer       B      A     D   D   C   C   D        C   A   C    C    B    A    A,C,D    3
                                                         Solutions DPP-05
1.     Ans. B
       Ionisation potential does not depend on atomic mass.
2.     Ans. A
       Successive Ionisation Potential of an element is always greater than previous one
                         ( )
                    IP3 M−
                    →M2(g+)
       (c) M(+g) ⎯⎯⎯⎯
3.     Ans. D
       Li         Be           B        C       N           O          F      Ne
                                                                                     L → R Z eff  
       2s1        2s2          2p1      2p2     2p3         2p 4       2p5    2p6     I.E.        
                                                                                                   
                                                                                      2    1       
                    s2 >p1                          p3 >P 4 (half filled)            s >p         
                                                                                        3    4
                                                                                     
                                                                                     p   >p       
                                                                                                    
       Li < B < Be < C < O < N < F < Ne → I. E.1
4.     Ans. D
       165, 195, 556, 595
       Here we get large Jump in I.E. value after removal of second electron so, it is clear that removal of third electron
       requires more energy. Hence, element 'X' should have 2 electron in its outer most shell.
       So, electronic configuration of X → 1s2 2s2 2p6
5.     Ans. C
                  N –3         O–2      Na+          Mg +2 → isoelectronic series
       Z          7            8        10           12
       e      10        10        10          10
       As value of Z increases, then Zeff increases which cause increase in IP.
       N 3− < O2− < Na+ < Mg 2+
       N 3− minimum
       Mg 2+ maximum
6.     Ans. C
       Sc                      Ti               V                   Cr               Mn
       4s 2 3d1              4s 2 3d2         4s 2 3d3             4s1 3d5          4s 2 3d5
                                                ↓    – e–
       4s1 3d1               4s1 3d2          4s1 3d3              4s 0 3d5         4s1 3d5
                                                                   ↓
                                                                   Due to half filled subshell more energy required to
                                                                   remove an electron from this.
7.     Ans. D
                                                1
       We know that Reducing power ∝
                                               I.E
                       Na             Mg                 Al
                       K
       I.E. →          Mg        >    Al    > Na > K
                                                        ——
                                                         
                                                     Minimum I.E
       Maximum Reducing power. Hence, strong reducing agent.
8. Ans. C
9.     Ans. A
       (A) IP of Zn > Mn
                d10        d5
       (B) IP of Xe > Ne
       (C) IP of Sc > Mn
                d1     d5
       (D) IP of Na > As
                  s1       p3
10.    Ans. C
       Second Ionisation potential order : Be < C < B < N < F < O < Ne < Li
11.    Ans. C
                 1
       I.P 
                size
12.    Ans. B
       Mg >       Al        P    > S       Noble gases having
       s2         p1        p3       p4    maximum due to ns2np6
       Stable          stable              stable configuration
13.    Ans. A
                              I.P.
           B             N
Al P
15.    Ans. 3
       E5+ contains zero electron. So, total electrons in E = 5
       Electronic configuration = 1s 2 2s2 2p1
       Valence shell electrons = 3
3.     Electron affinity is a :-
       (A) Relative strength to attract the shared electron pair
       (B) Necessary energy required to remove the electron from the ultimate orbit
       (C) Energy released when an electron is added to the outermost shell
       (D) Energy released when an electron is added to the inner shell
4.     Which of the following electronic configuration is expected to have highest electron affinity :-
       (A)   [He]2s 2 2p0
       (B)   [He]2s 2 2p2
       (C)   [He]2s 2 2p3
       (D)   [He]2s 2 2p1
5.     Select the correct code in terms of true (T) and false (F), respectively.
       (i) Process of adding electron to an atom may be exothermic or endothermic.
       (ii) In most of the elements energy is released when an electron is added to the atom.
       (iii) Halogens have maximum ∆𝐇𝐞𝐠 in their respective period because of their stable electronic
             configuration.
       (iv) Electron affinity order S < O
       (v) ∆𝐇𝐞𝐠 is maximum positive for inert gases in their respective period
       (A) T F F T F
       (B) F T T F T
       (C) T T F F T
       (D) F F F T F
7.     If ∆𝐇𝐞𝐠 of
       (Oxygen)           O = a KJ/mol             𝐎+ = b KJ/mol
       (Sulphur)          S = c KJ/mol             𝐒 + = d KJ/mol
       Then find correct order of ∆𝐇𝐞𝐠 ?
       (A)   a>c>b>d
       (B)   a>c>d>b
       (C)   b>d>c>a
       (D)   b>d>a>c
8.     Ionisation energy of F- is 320 kJmol-1. The electron gain enthalpy of fluorine would be :
       (A) -320 KJ/mol
       (B) -160 KJ/mol
       (C) +320 KJ/mol
       (D) +160 KJ/mol
13.    The element having very high ionization enthalpy but zero electron gain enthalpy is :
       (A) H
       (B) F
       (C) He
       (D) Be
14.    The following of the oxide ion O2- (g) requires first an exothermic and then an endothermic step as shown
       below :
       O(g) + e− → O− (g); H = − 142kJmol−1
       O(g) + e− → O− (g); H = 884kJmol−1
       (A) O- ion has comparatively larger size than oxygen atom
       (B) Oxygen has high electron affinity
       (C) O- ion will tend to resist the addition of another electron\
       (D) Oxygen is more electronegative
       If electronic configuration of element A is [𝐍𝐞]𝟑𝐬 𝟏 , then which of the following order is correct regarding
       given enthalpies ?
       (A)   |∆H4 |   =   |∆H5 |
       (B)   |∆H2 |   >   |∆H1 |
       (C)   |∆H2 |   >   |∆H3 |
       (D)   |∆H1 |   =   |∆H6 |
Answer Key
  Question      1     2     3   4   5   6    7       8   9   10   11   12   13   14
  Answer
                                                     Solutions DPP-06
1.     Ans. C
       EA of Cl > EA of F
2.     Ans. B
       O(g) +e- ⎯⎯
                 → O-(g) ; ΔH=-x
       O-(g) +e- ⎯⎯  2-
                  → O(g) ; ΔH=+y                        → Energy is required to add one electron to O1-
       O(g) +2e- ⎯⎯
                  → O-2
                     (g) ; ΔH= y - x =positive → Because y > x
3.     Ans. C
       It is amount of energy released when an electron is added to the outermost shell of an isolated gaseous atom.
4.     Ans. B
       When electron is added to [He]2s22p2 then the configuration formed is very stable [He] 2s22p3. Thus, energy
       released for this addition of clectron will be maximum.
5.     Ans. C
       (i) Electron gain Enthalpy may be exothermic or endothermic.
       (ii) Addition of first electron is exothermic process for most of the elements.
       (iii) Halogens have maximum ∆Heg in their respective period as ∆Heg increase across of the period Due to
            more Zeff and not due to stable configuration.
       (iv) S > O; E A (3rd period > 2nd period)
       (v) ∆Heg = positive for noble gases due to their stable configuration.
6.     Ans. A
       (A) ∆Heg order
        F < F + } Positive charge More attraction
       Cl < Cl+
                                           1
       I.E. of F > I.E. of Cl I.E. 
                                       no.of shell
       & |I. E of F| = |ΔHeg of F + |
       |I. E of Cl| = |ΔHeg of Cl+ |
       So, ∆Heg of F + > ∆Heg of Cl+
       ∆Heg of Cl > ∆Heg of F
       Correct order of ∆Heg ⟹ F + > Cl+ > Cl > F
7.     Ans. D
       ΔHeg of O < O+
                          } Positive charge → More Attraction → more ΔHeg
        ΔHeg of S < S +
       ∆Heg of S > O
       I.E. of O > I.E. of S
       |I. E. of O| = |ΔHeg of O+ |
       |I. E. of O| = |ΔHeg of O+ |
       |I. E. of S| = |ΔHeg of S + |
        Heg of O+ > ∆Heg of S+
       Then correct order
       O+ > S + > S > O (∆Heg )
       b>d>c>a
8.     Ans. A
       IE of F- = - Heg of F
       So ans is -320 KJ/mol
9.     Ans. D
       Across the period, electron affinity increases. Also, electron affinity of fully filled and half-filled configuration is
       minimum. So, correct order is : Cl > S > Si > P
10.    Ans. D
       Li          Be             B                C               N               O              F
       1s 2s
          2 1
                   1s 2s
                      2 2
                               1s 2s 2p
                                 2 2    1
                                              1s 2s 2p
                                                2 2    2
                                                                1s 2s 2p
                                                                  2 2    3
                                                                               1s 2s 2p
                                                                                 2 2    4
                                                                                              1s 2s 2p5
                                                                                                2 2
       Li →gaining one e–, it completed full filled configuration while boron does not therefore Li has more electrons
       affinity then B.
       Be → Full filled, E. A – almost Zero
       B → I.P. of Be is more as compare to B due to full filled configuration
       C → gaining one e– it is completed half-filled configuration
       N → half-filled easily not accept the electron
       F → gaining one e– it is completed full filled configuration
11.    Ans. B
       Given:
                        O (g) + 2e– ⎯→ O2– (g) Heg1 = 639 kJmol–1
                        O (g) + e– ⎯→ O– (g) Heg2 = –141 kJmol–1
       Subtracting:     O– (g) + e– ⎯→ O2– (g) Heg1 = 639 + 141 = 780 kJmol–1
12.    Ans. C
       Electron gain enthalpy of N < O and Al < Cl also N < Al as nitrogen is half filled.
       We know
                Heg O > B and B > Al
       So,      Heg O > Al
       Also,    Heg Cl > O
       Hence, overall order : N < Al < O < Cl
13.    Ans. C
       He, having very high Ionisation enthalpy but zero electron gain enthalpy because 1s is completely filed.
14.    Ans. C
       2nd EA is always endothermic process due to repulsion between negatively charged electron and O – ion.
15.    Ans. C
       1) Basic nature decreases across the period.
       2) Correct second ionisation potential order : Na > S > P > Si
5.     Among the following least and most polar bonds are respectively :-
       (a) C – I                (b) N – O                      (c) C – F              (d) P – F
       (A) d and c
       (B) a and d
       (C) b and d
       (D) b and c
8.     The values of electronegativity of atoms A and B are 1.20 and 4.0 respectively. The percentage of ionic
       character of A–B bond is :
       (A) 50%
       (B) 72.24%
       (C) 55.3%
       (D) 43%
9.     The electronegativity of A is 0.7 and that of B is 4.0. The bond formed between is :
       (A) Electrovalent
       (B) Covalent
       (C) Metallic
       (D) None
Passage 15 to 19
       Ionization energies of five elements in Kcal/mol are given below
20.    I.P. of an element is equal to 14.2 eV and EA is equal to 2.6 eV, then find electronegativity according to
       Pauling scale.
Answer Key
 Question    1    2    3    4   5   6   7   8     9   10     11   12   13   14   15   16   17   18 19 20
 Answer      B    A    C    D   B   C   B   B     A   C      C    C    C    C    B    B    C    A   C    3
                                                 Solutions DPP-07
1.     Ans. B
       (EN)C > (EN)Si ; (EN)Cl >(EN)C
2.     Ans. A
       Order of EN : Bi < P < S < Cl
3.     Ans. C
       EN order H > Li > Na
4.     Ans. D
       F > O > Cl > S > H (From Pauling scale)
5.     Ans. B
       As electronegativity difference increases then bond polarity increases.
       C – I = |2.5 – 2.55| = 0.05 minimum bond polarity
       P – F = |2.1 – 4| = 1.9 Maximum bond polarity
6.     Ans. C
       % Ionic character = 16|∆EN| + 3.5 (∆EN)2
        ∆EN = 2.6 – 1.8 = 0.8
           = 16 |(0.8)| + 3.5 (0.8)2
           = 15.04%
7.     Ans. B
       EN = 4 – 0.7 = 3.3
       % ionic character = 16 |∆EN| + 3.5 (∆EN)2
       = 16 |3.3| + 3.5(3.3)2
       = 93.225%
8.     Ans. B
       %Ionic character = 16 + 3.52
        = | X A − XB |
        = | 4 − 1.20 |
        = 2.8
       %I.C. = 16 x 2.8 + 3.5 x (2.8)2
       = 44.8 + 27.44
       = 72.24%
9.     Ans. A
       EN = 4 – 0.7 = 3.3
       as EN > 2.1
       So, electrovalent bond.
10.    Ans. C
       Carbon is more Electronegative among given elements.
11.    Ans. C
       X+Y- is ionic
       So (EN)x < (EN)y
12.    Ans. C
       Element with more electronegativity is written in the end. So, iodine chloride.
13.    Ans. C
       (A) F, Cl  EN = | 4 – 3.16 | = 0.84
       (B) C, H  EN = | 2.55 – 2.2 | = 0.35
       (C) P, H  EN = | 2.19 – 2.2 | = 0.01
       (D) Na, Cl  EN = | 0.93 – 0.79 | = 0.14
       EN for P-H is minimum among the given pairs.
14.    Ans. C
              IP + EA
       EN =
                 2
       So, 2 EN – IP – EA = 0
15.    Ans. B
       Ist IE of noble gas is very high
16.    Ans. B
       The element with low value of first IE and very high value of second IE forms stable unipositive ion.
17.    Ans. C
       The element having low value of IE for removal of initial two electrons and very large IE value for removal of
       third electron, will form stable oxidation state +2.
18.    Ans. A
       The element with highest first ionisation energy among the given is more electronegative.
19.    Ans. C
       Most electropositive : Lowest 1st IE
20.    Ans. 3
             IP + EA 14.2 + 2.6 16.8
       XP =         =          =     =3
               5.6      5.6      5.6
6.     Which of the following sequence correctly represent the decreasing acid nature of oxides ?
       (A) Li2O > BeO > B2O3 > CO2 > N2O3
       (B) N2O3>CO2>B2O3>BeO>Li2O
       (C) CO2 > N2O3 > B2O3 > Li2O
       (D) B2O3 > CO2 > N2O3 > Li2O > BeO
9.     An element ‘X’ which occurs in the first short period has an outer electronic structure s 2p1. What is the
       formula and acid -base character of its oxides :
       (A) XO3, basic
       (B) X2O3 basic
       (C) X2O3 acidic
       (D) XO2 acidic
12.    Compounds whose aqueous solution is acidic and order of their acidic strength
       (A) AOH, COH ;     AOH < COH
       (B) HDO, HBO ;     HDO > HBO
       (C) AOH, COH ;     AOH > COH
       (D) HDO, HBO ;      HDO < HBO
13.    Compounds whose aqueous solution is basic and order of their basic strength
       (A) AOH, COH ;      AOH < COH
       (B) HDO, HBO ;     HDO > HBO
       (C) AOH, COH ;      AOH > COH
       (D) HDO, HBO ;      HDO < HBO
Answer Key
Question 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Answer C B C D A B D A C B B B A 4
                                                 Solutions DPP-08
1.     Ans. C
       ClOH > BrOH > IOH (Same group)
       Generally, In a group top to bottom electronegativity decreases so Acidic Character decreases.
2.     Ans. B
       Order of Acidic strength
       Mn2 O7 > MnO2 > Mn2 O3 > MnO
       more electronegativity  more acidic strength
3. Ans. C
4.     Ans. D
       Oxides of Zn, Al, Be , Ga, Pb, Sn are amphoteric in nature.
5.     Ans. A
       Metal Oxides are Basic in nature.
       Na2O > BaO > FeO > Fe2O3
6.     Ans. B
       Across the period, EN increases so acidic strength increases.
7.     Ans. D
       In M(OH)2
       Lower the electronegativity of M, more will be basic strength.
8.     Ans. A
       CO is neutral oxide.
9.     Ans. C
       Valence electrons of X = s2p1  Cation formed = X3+
       So, oxide formed = X2O3.
       Across the period, acidic strength increases, so this oxide will be acidic.
10.    Ans. B
       Down the group, basic nature increases and across the period, basic nature decreases.
       So, Al2O3 < MgO < Na2O < K2O
11.    Ans. B
       Down the group, acidic strength of hydra acids increases.
12.    Ans. B
       A + O − H → A+ + O̅H            (Base)
       A − O − H → AO + H +
                       –
                                       (Acid)
       AOH            |XO – XA ||XO – XH |
                         |3.5 – 1.8|       |3.5 – 2.1|
                                           1.7 > 1.4 Base
       BOH               |XO – XB ||XO – XH |
                         |3.5 – 2.6|       1.4
                                           0.9 < 1.4 Acid
       COH               |XO – XC ||XO – XH |
                                           1.9 > 1.4 (Base)
       DOH               |XO – XD ||XO – XH |
                                           0.7 > 1.4 (Acid)
       (D-O bond is less polar than B-O)
13.    Ans. A
       A − O − H → A+ + OH –           Base
                       –    ⊕
       A − O − H → AO + H              Acid
       AOH            |XO – XA ||XO – XH |
                |3.5 – 1.8|       |3.5 – 2.1|
                                  1.7 > 1.4 Base
       BOH               |XO – XB ||XO – XH |
                |3.5 – 2.6|       1.4
                                  0.9 < 1.4 Acid
       COH               |XO – XC ||XO – XH |
                                  1.9 > 1.4 (Base)
14.    Ans. 4
       Basic → CsOH, Sr(OH)2 , Ca(OH)2 , Ba(OH)2 , NaOH
       OC(OH)2 → H2 CO3 → Carbonic Acid (Acid)
       SO2 (OH)2 → H2 SO4 → Sulphuric Acid (Acid)
       BrOH → Acidic
       O2 NOH → HNO3 → Nitric acid (Acid)