CHEMISTRY CLASS

GRBNEW ERA
192
COMPETITION KIT
X(PARTA
incorrect)
Which of the following statements is
11, (a) The charges on an electron and a proton are equal
OBJECTIVE QUESTIONS opposite.
no charge.
Following objective questions have (b) Neutrons haveprotons have the same mase
fo Electrons and neutron are nearly
only one correct alternative. a proton and a
(d) The mass of
the atoms of:
the sanme,
1, The ratio of elm for a cathode ray: 12. Isobars are number
(a) varies with a gas in a discharge tube having same atomic
(a) same elements mass
having same atomic
Yis fixed (b) samne elements same atomic mass
having
(c) varies with different electrodes eY differentelements
(d) is maximum if hydrogen is taken above
(d) none of the represents isobars2
pair
2. Cathode rays are: 13. Which of the following
(a) electromagnetic waves (b) Mg and Mg
(b) stream of a-particles (a) He and He
fo stream of electrons Ca (d) 19 KandK
(e)1gK and
(d) radiations rays produced in a vacuum
3. Which is the correct statement about a
proton? 14. The nature of positive discharg
tube depends upon:
(a) It is nucleus of deuterium. filled
(b) It is ionised hydrogen molecule. (a) the nature of the gas
Ves It is ionised hydrogen atom. material of cathode
(b) nature of the
(d) It is oa-particle. (c) nature of material of
anode
because:
4 The discovery of neutron came very late electrodes
(a) it is present in nucleus (d) the potential applied across the
(b) it is a fundamental particle 15. The ratio of energy of radiations of wavelengths 2000
(c) it does not move and that of 4000 ¢is:
(b) 4
d) it does not caTy any charge (a) 2 1
5. The radius of an atomic nucleus is of the order of: 1
(d)
(a) 100 cm (by 10-13 cm 4
(c) 10- cm (d) 10 cm 16. Which of the following statements is incorrect?
of elm of anode rays has been observed (a) The frequency of radiation inversely proportional o
6. The highest value
when the discharge tube is filled with: its wavelength.
(b) Oxygen (b) Energy of radiation increases with increase in
(a) nitrogen frequency.
(CYhydrogen (d) helium (c) Energy of radiation decreases with increase in
7. Which of the following atoms contain least number of wavelength.
neutrons?
(d) The frequency of radiation is directly proportional to is
238U
(b) 92 wavelength.
17. Out of X-rays, visible, ultraviolet, radiowaves, the larges
(c) Np (d) Np frequency is of:
8. Which of the properties of the elements is a whole number? (a) X-rays (b) visible
(a) Atomicmass (by Atomic number (c) ultraviolet (d) radiowaves
(c) Atomic radii (d) Atomic volume 18. The wave number which corresponds to electromagnebe
9. Increasing order (lowest first) for the values of elm radiation of 600 nm is equal to:
(charge/mass) for electron (e). proton (p), neutron (n) and (a) 1.6xi0 cm-! (b) 016x10 cm
a-particle (a) is: (c) 16x10 cm-! (d) 160 x10 cm-1
(a) e, p, n, a (b) n, p, e, a 19. Different lines in Lyman series of hydrogen spectrum uo
(c) n, p,a, e (a n, a, P, e (a) UV
(b) Visible
10. Isotopes of an element have: (c) IR (d) far IR
(a) different chemical and physical 20. Which one of the following is not the characteristic o
(b) similar chemical and physical properties
properties
(csimilar chemical but different physical properties Planck's quantum theory of radiation?
(a) The energy is not absorbed or emittedin wholee number
(d) similar physical and different
chemical properties multiples of quantum number.

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STRUCTURE OF ATOMaio Ana WaM aRo 193

Radiation is associated with enargy. (o)aspectrum of hydrogen molecule

ie) Radiation energy is not emitted or absorbcd (uesplar spectrum electronic
continuously but in the form of small packets called 31, The/ wavelength of a spectral line for an
quanta. transition is inversely related to:
undergoing transition
)The magnitude of energy associated with a quantum is (a) number of electrons atom
proportional to the frequency. (b) the nuclear charge of the undergoing transition
The spectrum of helium is expected to be similar to that of: (c) the velocity of an electron levels involved in the
(a) H (b) Na odt C the difference in the energy
(c) He* transition
to the radiation emítted by
32 Energy of
Bohr'sorbit: 32. The spectral lines corresponding
5, 4th orbit to second orbit
(hcreases as we move away from the nucleus an electron jumping from 6,
0) decreases as we move away from the nucleus ob belong to:
(b Balmer series
ic) remains the same as we move away from the nucleus (a) Lyman series (d) Pfund series
(d) none of the above atar (C) Paschen series spectrum, which electronic
Which of the following statements does not form part of 33. In Balmer series of hydrogen [PMT (MP) 2000]
Bohr's model of the hydrogen atom? transition causes third line? aeio
(a) Energy of the electron in the orbit is quantised. (a) Fifth Bohr orbit to second one noiA(o
the Ab
b) The electron in the orbit nearest to the nucleus has (b) Fifth Bohr orbit to first oneslogul
first one
lowest energy.
nucleus. 6to (C) Fourth Bohr orbit to
(c) Electrons revolve in different orbits around (d) Fourth Bohr orbit to second
one
(The position and velocity of the electron in the orbit and speed of the electron in
34. The ratio of the velocity of light ground state is (c is
cannot be determined simultaneously the lst orbit of the hydrogen atom in the
to a
24 When an electron drops from a higher energy level the velocity of light):
lower energy level, then: (a) 1.37 (b) 1370 siio thob
(a) energy is absorbed (c) 13.7 (d 137
bsalunog
non 0 ono d number is related to:
energy is emitted 35. The magnetic quantum
(c) atomic number
increases (a) size (b) shape
(d) atomic number decreases 39n (c) orientation (d) spin
the 3rd orbit is: number represents:
25. On the basis of Bohr's model, the radius of {36. The principal quantum
(a) equal to the radius of first orbit
(a) shape of an orbital
orbitoMI (s (b) number of electrons in an orbit
(b) three times the radius of first
(c) five times the radius of first orbittfsM! (o c) distance of electron from nucleusonnse odn.8
(Y nine times the radius of first orbit P (d) number of orbitals in an orbit
electron in 2s -orbital
26. The ratio of 2nd, 4th and 6th orbit of hydrogen atom is: 37. The orbital angular momentumn of an
(IT 1996)
(a) 2:4:6 6Y1:4:9 is:
(d) 1:2:3
(c) 1:4:6
atom? (a) +. 1 h
21. Which point does not pertain to Bohr's model of 2 2T
h/2. hiogsE (Cciros
(a) Angular momentum is an integral multiple of h d) N2
(b) The path of the electron is circular. (c)
2
(c) Force of attraction towards nucleus = centrifugal force.
38. The atomic orbital is:
Theenergy changes are taking place continuously.
a According to Bohr's theory, the angular momentum for an (a) the circular path of the electron
electron of 5th orbit is:is o (AIEEE 2006; UPSEE 2011) (b) elliptical shaped orbit
(c) three-dimensional field around nucleus probability of
(a y the region in which there is iomaximum
finding an electron e 20 sis2
25hsidnos l
(cl=5ndiu t (d) 39. The maximum number of electrons on a principal shell are:
(a) n2 (b) n
D. The energy of an electron in the first Bohr's orbit of H-atom le 2n2 (d) 3n2
S-13.6 eV. The possible energy values of the excited state
(5) for the electrons in the Bohr's orbits of hydrogen is 40. Any p-orbital can accommodate upto:
(are) (IIT 1998)
(BCECE 2005; J&K 2005)
-3.4eV (b) - 4.2 ey (c) -6.8 eV (d) + 6.8 eV (a) 4 electrons
30, Bohr's model can explain: (b) 2 electrons with parallel spins
(a) pectrum of hydrogen atom only (c) 6 electrons
spins otafe ehi. h
Spectrum of any atom or ion having one electron only )2 electrons with opposite

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 CHEMISTRY CA
194 GRB NEW ERA CLASS X
e
correct sequence for fillng of elecc
41. The total number of orbitals in a principal shell t S4. Ifn= 6, the
(a) (c) 2,2 (dy34 np’n -)d (n-2)
42 What is the maximum number of electrons thr can be (a) ns (n-)f’(n-) d ’np
sCCommxodated in an atom in which the highest principal b ns (n- 2)f’np
quantum number value is 4? (c) ns (n-)d’ (n-1)d
[PMT (MP)2000] ’ np ’
(a) 10 (b) 18ol (d) ns- (n-2f contant is 107
value of Rydberg
(es 36
(d)54 55. Given the line of the Balmer series in
number of the last
43. When the azimuthal quantum number has the value of 2, the
number of orbitals possible are:
(a) 3 (b) 0
(CET (Karnataka) 2008]
spectrum will be:
(a) 2.5xX10'm-! (b) 0125x1 wyenga
m
(c) 7 (c) 0.5x10m-1
S6. Ifthere are three electrons in psubshel. which oe
44. Out of the following options which one can be used to
accommodation of
produce a propagating electromagnetic wave ? following ís the correct thee deosnO
(NEET-1 2016)
(a An accelerating charge
(b) A charge moving at constant velocity
electrons are there in N2
(c) A stationary charge 57. How manyi unpaired (b) 8 (Z=p
(d) Achargeless particle (a) Zero
45. Which one of the following orbitals, has shape of a (d) 4
baby-soother?
h (e 2 orbital:
58. The energy is lowest for the
(ay d,y (b) d (a) 3d (b) 4p
(d) ) (d) 4f
Pyo tt 59. (ey
In 4s
chromíum atom (Z = 24), the number of orbi
46. A 5f-orbital has: [MEE (Kerala) 2000] populated by one or more electrons are:
(a) one node (b) two nodes (b) 14
fdy four nodes Aa) 15
(c) three nodes (d) 10
47. Which one of the following electronic configurations is not (c) 12
possible?
60. The electronic configuration of chromium (Z= 24) i
(a) 2p (b) 3s 1 (BCECE 2005, AMU Z05
Sey2d 5 (d) 4f 12 (a) (Nej 3s23p"3d *4s? (by (Ne) 3s'3p'34'4
(c) [Ne]3s'3p^3d '452 (d) [Ne] 3s'3p°4s'4yt
48. The magnetic quantum number for valency electron of
sodium atom is: 61. The number of unpaired electrons in the cdecro
(b) 2 do configuratíon 1s', 2s2p* is:
(a) 3
(c) 1 (dyzero (a) 6 (b) 2
49. The shape of the orbital isgiven by: (c) 4 (d) 3
(a) spin quantum number 62. If the electronic structure of oxygen atom is writes
(b) magnetic quantum number 2p
(c) azimuthal quantum number
(d) principal quantum number it would víolate:
50. The energy of an electron of 2p,-orbital js:
(a) greater than 2p, -orbital T (a) Hund's rule
(b) less than 2p, -orbital (b) Pauli's
exclusion principle
(c) equal to 2s -orbital (c) both Hund's and Pauli's principles
(d) sarne as that of 2p, and 2p, -orbitals (d) none of the above
S1. The maximum number of electrons in a subshell is given by 63. The orbital ldiagram in which 'Aufbau principle isviolael
the expression: is:
(aY41+2 (b) 4/-2 nO 2s
(c) 21+1 2p
o (d) 2n
52, An electron has a spin quantum number +1/N and a
magnetic quantum number -l. t cannot be present in:
(a) d-orbital
(a)4t
(b) f-orbital
4e s-orbital (d) p-orbital
$3. A new electron enters the orbital when:
{a) (n+ l) is minimum (b) (n+ l) is
(c) (n+m) is minimum (d) (n+ m) is maximum (d)
maximum
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sTRUCTURE OF ATOMHO 195
Which of the following elements is represented by the 75. Rutherford's experiment whichof:established the nuclear
electronic configuration? model of the atom used a beam (uT 2002)
(a) B-particles, which impinged on a metal foil and oot
2 qtg (d ollao nabsorbed to odnan R
(b) Y-rays, which impinged on a metal foil and ejected
ls‘ electrons a5noto
bos (c) helium atoms, which impinged on a metal foil and got
Jooscatteredkoiept
(a) Nitrogen (by Fluorine (Yhelium nuclei, which impinged on a metal foil and got
scattered
(c) Oxygen (d) Neon
& Kvpton (At. No. 36) has the electronic configuration 76. If the nitrogen atom had electronic configuration 1s, it
IArl 4s 3d "4p°.The 37th electron will go into which one would have been lower than that of normal ground state
of the following sub-levels? configuration 1s", 2s2p° because the electrons would be
(a) 4fouupet s (b) 4d closer to the nucleus. Yet ls' is not observed, it violates:
(c) 3p (uIT 2002)
K An ion which has 18 electrons in the outermost shell is: oHE (a) Heisenberg's uncertainty principle
(a) K+ (b) Hund's ruleot l nu honals al o
(c) Cs (d) Th+pix dcà(6) 800-(e) Pauli's exclusion principle
. Which of the following has the maximum number of (d) Bohr's postulate of stationary orbits
unpaired electrons? i e golovew botsioo(uT1996) 77. In Bohr series of lines of hydrogen spectrum, the third line
(a)Mg2+ SESE from the red end corresponds to which one of the following
(b) Ti*ixèàqdto RoRs inter-orbit jumps of the electron for Bohr orbits in an atom
(c) v* of hydrogen?() (AIEEE 2003)
& If the electron falls from n=3 to n = 2, then emitted energy (a) 5 ’ 2 (b) (b) 4’1
t u nicoeo 1odnin s (AFMC 1997) io rn (c)2550b atneomsist a) 3’2 lo doidW.8
(a) J0.2 eV gaiw (b) 12.09 eVissh 78. Which one of the following ions has electronic
e 1.9 eV (d) 0.65 eV i (s) H4. configuration [Ar]3d °?rioitsto i (CBSE (PMT) 2010]
69. For a d-electron, the orbital angular momentum is:
Oaroacn) dges oIslus (iT 1997) (c) Febtgaicdo
3+
b) V2. i0915hih (d) Co+
2T 29 79. The de Broglie wavelength of a tennis ball of mass 60 gm
h h a SE008)
(C
2T
(d) moving with a velocity of 10 metre per second, is
70. The electrons, identified by quantum numbers n and 1,
ai(eon:
so (a)
approximately;
10-31
ot (mq ni) siba sldugongi (AIEEE 2003)
(b) 10-16
metre metre
()n=4,l=1(i) n=4, 1l=0(ii) n3,1=2 (iv) n=3, l=1 (c) 10 metre.(d)a (d) 10-33 metre,0i
can be placed in order of increasing energy, from the lowest
to highest, as: (IT 1999) (Planck's constant, h=6.63 ×10-34 J s)
(a (iv) < (iü) < (üi) < (i) (b) (ii) < (iv) < ())< (iüi) 80. A proton is about 1840 times heavier than an electron.
(c) ) < (m) < (i) < (iv) (a) (iii) < (i) < (iv) < (i) When it is accelerated by a potential difference of l kV, its
1L The number of nodal planes in p, -orbital is: kinetic energy will be:
(1T 2000) (AlIMS 2003)
aYone UR o ro (b) two o2ds (a) 1840 keVgie b) (b) 1/1840 keV
(c) three o 32 coiaing si (d) zero2tgrslorE (o1 keyi sli lo brfiw () 920 key nl
12 The electronic configuration of an element is: 81. Which of the following is not a permissible arrangement of
1s,2s 2p,3s3p 3d,4s' electrons in an atom?lo (AIPMT 2009)
This represent its: (IT 2000) (a) n=5, l=3, mn = 0, s = +
(a) excited state fb) ground state (b n=3, l=2, m=-3, s=
(c) cationic state (d) anionic state (c) n=3, l=2, m=-2, s =
13. For how
many orbitals, the quantum numbers (d) n =4, l=0, m= 0, s=
h=3,l=2, m=+2 are possible?[CBSE (Med.) 2001] 82. Magnitude of kinetic energy in an orbit is equal to: 2005)
(9)1
(c) 3 (b) 2 (BCECE

4. (d) 4 (a half of the potential energy

ldentify the least stable among the
(a) Li
Abj
following:
Be
(IT 2002) (b) twice of the potential energy
(c) one-fourth of the potential energyEO
(c) B
(d) C (d) none of the above

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 CHEMITRY
GRA NEW ERA CLASS
X(PARTA
STRUC
196
92, The orlentatlon of an atomie orbltal is governed by.
102. 7

Observe the tollowing statements regarding Isotones: quantum number

CaSE (Med,) 2
Kand aare isolonex. (a)magnetic quantum number
. Nucides having different atomic nunber () and mas (b) princlpal quantum number
umber (4) but sane number of neutrons are called (c) azimuthal number
spin quantum
93, (d)Which of following angular momentum is not ponible
IL. F and 2 Na are isotones. theory?
The onet answer is: (EAMCET (Medical) 2005) according to Bohr's 103,
(a) 1, I and lll are cow sb) only Iand Il are corret (b)
(C) only land lil are cort(d) only ll and lllaro (a)
2T h
atom , The
64 lonization energy of He is 196xL0 8 J (c)2,s 3T
(
eeyy of the tirst stationary state = )of Li" 0s: enthalpy of hydrogen 104
x10 J mol- , The energy required to alom
ionization
(a) - 2.2x 10-15 J atom (b)8.82 x 10" J atom 94. The
1,312 excite te
n=lto n 2 is:
(c) 4.41x 10 l J atom -! (d) - 4.4lx10-" J atom electron in the atom fron (AIEEE 200A
-13.6 eV, The mol-! (b) 8.51 x10 J mo|-!
8S, The enengy of electron in first Bohr's orbit is Aa) 9.84 x10 J
energy of the electron in its first excited state is: 6.56x 10 J mol! (d) 7.56 x 10 J mol-!
JEE (Orissa) 2005] 95, (c)
A 0.66 kg ball is moving with speed of 100 m/sec. The
(a)-34 eV (b) -27.8 eV
will be: 10
(c)-6.8 eV (d) - 10.2 eV 0001 associated wavelength
sec) (CBSE (PMT) Mains 20101
(h=6.6 x10- J
8o. Which of the following transitions have minimunm (b) 6.6x 10-34 m
wavelength? (DPMT 2005) (a) 6.6x10° m
lx10-32 m
(b) n2 n VD (c) lx10-3S m o s ( d )
(c) n4 n (d) n n Maximum number of electrons in a subshell of an atr
96.
87. Which of the following statements does not form a part of determined by the following: (AIPMT 2009)
Bohr's model of hydrogen atom? (DCE 2005) (a) 21+1 (b)4/+2
(a) Energy of the electrons in the ortbit is quantised. u (d) 4l+1
(b) The electron in the orbit nearest to the nucleus has the (c) 2n²
lowest energy. 97. Calculate the wavelength (in nanometer)
-1
associated with a
(c) Electrons revolve in different orbits around the nucleus. proton moving at lx10 msec
(d) The position and velocity of theelectrons in the orbit (AIEEE 2009)
(a) 0.032 nm (b) 0.40 nm
cannot be determined simultaneously.n (c) 2.5 nm (d) 14 nm
88. The most probable radius (in pm) for finding the electron in 98, In an atom, an electron is moving with a speed of 600 m/se
He is: (AlIMS 2005)
(a) 9.9 (b) 52.9
with an accuracy of 0.005%, Certainty with which the
position of the electron can be located is :
Ae) 26.5 (d) 105.8 (h=6.6x10-34 kg ms mass of electroa
89, The ratio of charge and mass would be greater for: m= 9.1x10-31 kg)
(BHU (Pre) 2005] (AIEEE 2009)
(a) 1.52 x10-4 m (b) 5.1x10 m
(a) proton (b) clectron
(c) neutron (d) alpha c(e1.92 x10-3 m (d) 3.84 x10- m
90. In a multi-electron atom, which of the following orbitals 99, A gas absorbs a photon of 355 nm and emits wo
described by threce quantum numbers will have the same wavelengths. If one of the emission is at 680 nm, the otht
energy in the absence of magnetic and electric fields? is at:
olooo (AIEEE 201)
(a) 518 nm (b) 1035 nm (c) 325 nm (dy743 nm
(AIEEE 2005)
() n=l, l= 0, m=0 (ii) n= 2, l=0, m=0 100. The electrons identified by quantum numbers 'n'
(iii) n= 2, I= 1, m =| A. n =4, l= 1 and"T:
(iv) n =3, l= 2, m l B. n = 4, I= 0
(v) n=3, I= 2, m=0 C. n =3, l=2
(a) (i) and (ii) can be placed in order of D. n = 3, l= 1
(b) (ii) and (ii)
(c) (ii) and (iv) (dy (iv) and (v)S8 increasing energy as:(AIEEE2012)
91. The de Broglie wavclength (a) A <C<B<D
Ikg having kinetic energy associated
0.5J is:
with a ball of mass (b) C < D< B<A
(a)6.626 x 10 m (b) 13.20 x 10-4
(AlIMS 2006)
m (oyD<B<C<A
101. Maximum number of electrons(d)inB< D<A<C
asubshell withl=3and
(c)10.38x10-21 m
(d) 6.626 x10-4 A ns4 is: [AIPMT(Pre)2012)
A) 14 (b) 16 (d) 12
(c) 10

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 srRUCTUREOFATOM
197
Calculate the cnergy in joule
a he t set of four quantum
is :
umbers for the valence 109.
wavelength 45 nm : (Planck':'s correspondi
constant ng 6.63 x10-
to the light of
htnn of ubidiunm atom (2 37) 2012; JEE (Main) 2014) Speed of light c =3 x10° ms-!) Js:
[AIPMT (Pre)
1 adl ay4.42 x10-l8 (b) 6.67 x10i5 (AIPMT 2014)
(b) 6, 0, 0, +; (c) 6.67x10!! (d) 442x10-15
110 What is the maximum number of orbitals that can be
() S, 1, 0, + identified with the following quantum numbers?
p-electron is given as:
a The obitalangular momentum of a [AIPMT (Mains) 2012]
(n =3, l=1, m, =0)
(AIPMT 2014)
(a) 4 (b)1
(c) 2 (d)3 l i o t s
(d)
2r 2 2r 111. Which of the following is the energy of apossible excied
a state of hydrogen? [JEE (Main) 2015)
M The kinetic energy of an electron in second Bohr's orbit of (a) + 6.8 eV (b) + 13.6 eV
(ITJEE 2012)
hogen atom is : (a is Bohr's radius) (c) -6.8 eVng (d-3.4 eVdb
(b) 112, The number of d-electrons in Fe (Z= 26) is not eaual to
47 mai 16r'ma, the number of electrons in which one of the following?
(AIPMT 2015)
)
32Rma
(d)
64ma) A) 01 (a) s-electrons in Mg (Z =1 2 ) A
(b) p-electrons in CI(Z = 17) dod ()
of electron is given by: 2 6 ) o ltA
Energy an
a (c) d-electrons in Fe (Z =
E=-2178x10 Wavelength of light required to (d) p-electrons in Ne (Z = 10)
113. The angular momentum of electron in d orbital is equal
excite an electron in an hydrogen atom from level n = 1 to (AIPMT 2015)
to:
atido
R=2 willbe: (h=6.62 x 10*J s and c=3.0 x 10 m s)
JEE (Main) 2013] (c) 2/3 (d) 0h
(a) 6.500 x 10 m (b) 8.500 x 10 m 1 114. Which is the correct order of increasing energy of the listed
ic) 1.214 x 10 m (d) 2.816 x 10 m
orbitals in the atom of titanium ? (At no. Z = 22)
IK The value of Planck's constant is 6.63 × 10 Js. The (AIPMT 2015)
peed of light is 3 x 1o!7 nm s .Which value is closest to (b) 4s,3s, 3p,3d
(a) 3s, 4s, 3p, 3d
the wavelength in nanometer of a quantum of light with
frequency of 6 x 10 s? sin ai mo(NEET 2013)
(c) 3s,3p, 3d, 4s (G) 3s,3p, 4s,3d
115. Two electrons occupying the same orbital are distinguished
(a) 25ut ts onun ) 50ho nà (A) E by: (NEET-1 2016)
(c) 75 (d) 10
. What is the maximum numbers of electrons that can be la) Spin quantum number
associated with the following set of quantum numbers?
(b)Principal quantum number n
(Given : n=3, l=1 and m = - 1 ) a(NEET 2013) (c) Magneticquantum number m
(a) 6 (b) 4
(d) Azimuthal quantum number l
(d) 10 116. Arrange the following electromagnetic radiations per
(72\ quantum in the order of increasing energy :
IR Based on equation E-2.178 x 10 J :certain si nA :Blue lightloanol B: Yellow light()
C:X-raycooS D: Radiowave
conclusions are written. Which of them is not correct? [JEE (Main) 2016]
(NEET 2013) v (a) D, B, A, C t 5do (b) A, B, D, C
(a) Larger the value of n, the larger is the orbit radius. boo (c) C, A, B,Doo (d) B, A, D, Co
(b) Equation can be used to calculate the change in 117. A stream of electrons from a heated flament was passed
when the electron changes orbit. energy
For n= 1, the electron has a more between two charged plates kept at a potential difference V
I does forn = 6 which means that negative energy than
the electron is more
esu. If e and n are charge and mass of an electron,
loosely bound in the respectively, then the value of h/2 (where Ais wavelength
0) The negative sign in smallest allowed orbit. associated with electron wave) is given by :
equation simply means that the
energy of electron bound [JEE (Main) 2016]
to the
Would be if the electrons were nucleus
at the
is lower than it (a) meV (b) 2meV
from the nucleus. infinite distance (c) VmeV (aY2meV

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