Entry Test Preparation 2015
Chemistry
BOOK 1
Chapter # 4
ATOMIC STRUCTURE
Direction
You are given following questions
from the topic, with four choices A through D. Select the choice that will
answer the question best.
1. The credit of discovering neutron goes to
A. Rutherford B. Langmuir
C. Chadwick D. Austen
2. The electronic configuration of O 2- is
A. 1s2, 2s2 ,2p4 B. 1s2,2s2,2p2
C. 1s2,2s2,2p3 D. 1s2,2s2,2p6
3. The number of electrons in the M shell of the element with
atomic number 24 is
A. 24 B. 12
C. 14 D. 8
4. The symbol of the element whose atoms
have the outer most electronic configuration 2s2 2p3 is
A. N B. Li
C. P D. Na
5. Which quantum number is sufficient to describe the electron
is hydrogen atom?
A. l B. n
C. m D. s
6. The valence orbital configuration of an element with atomic
number 23 is
A. 3d5 B. 3d3, 4s2
C. 3d3, 4s1, 4p1 D. 3d2, 4s2, 4p1
7. The spectrum of helium is expected to be similar to that of
A. H B. Li+
C. Na D. He+
8. If atomic number of nickel and copper
are 28 and 29 respectively. Which of the following does the electronic
configuration 1s2 2s2 2p6 3s2 3p6
3d10 represent?
A. Cu+ B. Cu2+
C. Ni2+ D. Ni
9. The radius of second Bohr’s orbit is
A. 0.053 nm B. 0.053/4 nm
C. 0.053 x 4 nm D. 0.053 x 20 nm
10. For which of the following sets of
quantum numbers an electron will have the highest energy?
A. 3,2,1, 1/2 B. 4,2,-1,
1/2
C. 4,1,0,-1/2 D. 5,0,0,1/2
11. Rutherford ’s experiment led
to the discovery of
A. Nucleus B. Electron
C. Proton D. 
- particle
- particle
12. Which of the following orbitals have a dumb bell shape?
A. s B. p
C. d D. f
13. Which of the following has more unpaired d-electron?
A. Zn+ B. Fe2+
C. Cu+ D. Ni3+
14. The de-Broglie wavelength of a particle with mass 1g and
velocity 1000 m/s is
A. 6.63 
10-34 m B. 6.63 10-33 m
10-34 m B. 6.63 10-33 m
C. 6.63 10-35 m D. 6.65 10-35 m
10-35 m D. 6.65 10-35 m
15. The energy of the first electron in helium will be
A. -13.6 eV B. -54.4 eV
C. -5.44 eV D. zero
16. They ionization energy of hydrogen is represented by
A. E
– E1 B. E2 – E1
– E1 B. E2 – E1
C. E3 – E2 D. E – E5
– E5
17. The wave number of the light emitted by a
certain source is 2 106 m-1.
the wavelength of this light will be
106 m-1.
the wavelength of this light will be
A. 500 nm B. 500 m
C. 200 m D. 5 107 m
107 m
18. Na+ has the following electron configuration
A. 1S2, 2S2, 2P6 B. IS2, 2S2, 2P6,
2S1
C. IS2, 2S2, 2P5,
2S1 D. IS2, 2S2, 2P4,
3S2
19. The value of charge on electron is
A. 1.602 10-19
coulombs B. 1.602 10-18
coulombs
10-19
coulombs B. 1.602 10-18
coulombs
C. 1.602 10-17
coulombs D. 1.602 10-16
coulombs
10-17
coulombs D. 1.602 10-16
coulombs
20. In Millikan method for determination of
charge on electron the air in the chamber ionized by
A. protons B. electric field
C. x-rays D. particles
particles
21. When electron moves with a velocity of
2.188 106 ms-1
then its wavelength is 0.33 nm, it is comparable to the wavelength of
106 ms-1
then its wavelength is 0.33 nm, it is comparable to the wavelength of
A. x-rays B. proton
C. -rays D. 
-rays
-rays D. -rays
22. Light emitted from a source has its wave
length 500 nm, then its wave number will be
A. 2 106 m-1 B. 2 107 m-1
106 m-1 B. 2 107 m-1
C. 5 108 m-1 D. 5 109 m-1
108 m-1 D. 5 109 m-1
23. For a 3P subshell the set of principal and azimuthal quantum
numbers is
A. n = 1, 1 = 2 B. n
= 3, 1 = 0
C. n = 3, 1 = 1 D. n
= 1, l = 3
24. The subshell filled first in the ascending order of their
energy is
A. 5d B. 5p
C. 5s D. 5f
25. If the value of azimuthal quantum number
is 3, then values of m the magnetic quantum no. will be
A. 0, 1, 2, 3 B. +3,
+2, +1, 0,-1, -2, -3
C. 0, -1, -2, -3 D. -3,
0, +3
26. The range of visible spectrum is
A. 300 – 600 nm B. 600
– 900 nm
C. 400 – 750 nm D. 100
– 300 nm
27. The maximum number of electrons in P orbital is
A. 2 B. 4
C. 6 D. 8
28. The value of spin quantum number is
A. +1/2 B. -1/2
C. +1/2 or -1/2 D. +2
29. Mass of an electron is equal to
A. 1.6 10-18 kg B. 9.1
10-19 kg
10-18 kg B. 9.1
10-19 kg
C. 9.1
10-30 kg D. 9.1
10-31 kg
10-30 kg D. 9.1
10-31 kg
30. Which rays are non material in nature?
A. 
-rays B. -rays
-rays B. -rays
C. -rays D. cathode rays
-rays D. cathode rays
31. Lyman series lies in
A. UV region B. visible
region
C. I.R. region D. microwave
region
32. f subshell has _______ orientations.
A. seven B. two
C. five D. four
33. When 3p orbital is complete, the entering electron goes into
A. 3d B. 4p
C. 4s D. 4d
34. In ground state, which element has one unpaired electron?
A. helium B. hydrogen
C. carbon D. oxygen
35. The orbital which can accommodate a maximum of 10 electrons is
A. f B. p
C. s D. d
36. Which of the following particles contains
20 neutrons. 19 protons and 18 electrons?
A. 
B. 
B.
C. 
D. 
D.
37. Atomic number of Na is 11. Number of
protons, neutrons and electrnos respectively present in sodium atoms is
A. 11, 11, 12 B. 11, 12, 12
C. 12, 11, 11 D. 11,
12, 11
38. Per centimeter is the unit of
A. Gas constant B. Planck’s
constant
C. Rydberg constant D. Boltzman
constant
39. Among the following, the electron with the highest energy is
A. n = 3, l = 2, m = 0, s = 
½
½
B. n = 4, l = 0, m = 0, s = ½
½
C. n = 4, l = 0, m = 1, s = ½
½
D. n = 3, l = 0, m = 0, s = ½
½
40. The number of nucleons present in the heaviest isotope of
hydrogen
A. 1 B. 2
C. 4 D. 3
41. X-rays are produced when cathode rays strike on
A. Graphite B. Carbon
C. Metal D. Non-metal
42. When an electron moves from an inner orbit to a higher orbit,
energy is
A. emitted B. absorbed
C. no charge in energy D. none of the above
43. Rutherford ’s scattering
experiment is related to the size of
A. Nucleus B. Atom
C. Electron D. Neutron
44. Which electronic level would allow the
hydrogen atom to absorb a photon but not to emit a photon
A. 3s B. 2p
C. 2s D. ls
45. The radius of the first Bohr’s orbit is
A. 5.29oA B. 0.529oA
C. 52.92oA D. 0.0529oA
46. Which one of the following series of
lines is found in the visible region of atomic spectrum of hydrogen
A. Balmer B. Paschen
C. Brackett D. Lyman
47. Isotope of copper with radioactive property is
A. Cu64 B. Cu62
C. Cu65 D. O16
48. Which rays of radioactive distingtegration ionize gases to the
maximum extent
A. -rays B. -rays
-rays B. -rays
C. -rays D. X-rays
-rays D. X-rays
49. Kinetic energy of -particle is much less than
-particle is much less than
A. -particles B. -particles
-particles B. -particles
C. all of these D. same
as both
50. Uncharged particles among the following
A. -rays B. -rays
-rays B. -rays
C. Cathode rays D. -rays
-rays
Chapter
# 4
ANSWERS
ATOMIC
STRUCTURE
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1
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C
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2
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D
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3
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C
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4
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A
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5
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B
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6
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B
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7
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B
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8
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A
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9
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C
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10
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B
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11
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A
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12
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B
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13
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B
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14
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A
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15
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B
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16
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A
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17
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A
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18
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A
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19
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A
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20
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C
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21
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A
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22
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A
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23
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C
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24
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C
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25
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B
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26
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C
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27
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C
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28
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C
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29
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D
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30
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B
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31
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A
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32
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A
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33
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C
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34
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B
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35
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D
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36
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A
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37
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D
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38
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C
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39
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A
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40
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D
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41
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C
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42
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B
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43
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A
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44
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D
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45
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B
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46
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A
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47
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C
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48
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A
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49
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A
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50
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D
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