# Atomic Structure Worksheet

Atomic Structure Worksheet

Atoms are made up of 3 particles electron, proton and neutrons. Each of them have different properties. Electrons are tiny, very light particles which have negative electric charge(-). Protons are larger and heavier than electrons and have opposite charge, protons have positive charges. Neutrons are large as protons. Neutrons are electrically neutral.

Worksheet Questions:

1.The ratio of specific charge of a proton and $\alpha$-particle is:

(a) 1 : 1
(b) 1 : 2
(c) 1 : 3
(d) 2 : 1

2. The heaviest particle is:

(a) Meson
(b) Neutron
(c) Electron
(d) Proton

3. The electron is identical with:

(a) $\alpha$-particle
(b) $\beta$-particle
(c) Deuteron
(d) Meson

4. Anode rays are:

(a) Electromagnetic waves
(b) Stream of anions
(c) Stream of positively charged particles
(d) Stream of electrons

5. Which of the following does not characterize X-rays?

(a) It causes ZnS to fluorescence
(b) It can ionize gases
(c) Deflected by electric and magnetic field
(d) Have wavelength shorter

6. Electromagnetic radiation with maximum wavelength is:

(a) Ultra violet
(c) X-ray
(d) Infra red

7. The charge to mass ratio (e / m) of an electron was determined by:

(a) Goldstein
(b) Rutherford
(c) Thomson

8. Which has more protons than electrons:

(a) $Na^+$
(b) $F^-$
(c) $Na$
(d) $O^{-2}$

9. Which is correct statement about proton:

(a) Proton is nucleus of deuterium
(b) Proton is an ionized hydrogen
(c) Proton is alpha particle
(d) Proton is ionized hydrogen atom

10. The quantum numbers +1/2 and -1/2 for the electron spin represent:

(a) Rotation of the electron in clockwise and anticlockwise direction respectively
(b) Rotation of the electron in anticlockwise and clockwise direction respectively
(c) Magnetic moment of the electron pointing up and down respectively
(d) Two quantum mechanical spin states which have no classical analogue

11. The frequency of a wave of light is $12 \times 10^{14}s^{-1}$. The wave number associated with this light is:

(a) $4 \times 10^4 cm^{-1}$
(b) $4 \times 10^{-8} cm^{-1}$
(c) $5 \times 10^{-7} cm^{-1}$
(d) $2 \times 10^{-7} cm^{-1}$

12. The nature of anode rays produced in a gas discharge tube depends upon the:

(a) Metal of electrode used
(b) Type of electric current passed
(c) Intensity of the electric field
(d) Nature of gas filled in the discharged

13. Neutron is a fundamental particle carrying:

(a) A charge of +1 unit and a mass of 1 unit
(b) No charge and a mass of 1 unit
(c) No charge and no mass
(d) A charge of -1 and a mass of 1 unit

14. Electromagnetic radiation with minimum wavelength is:

(a) Infra red
(b) Cosmic rays
(c) X-rays
(d) Ultra violet rays

15. The density of the neutrons is of the order of:

(a) $10^3 kg cm^{-3}$
(b) $10^6 kg cm^{-3}$
(c) $10^9 kg cm^{-3}$
(d) $10^12 kg cm^{-3}$

16. The mass of neutron is of the order of:

(a) $10^{-23}kg$
(b) $10^{-24}kg$
(c) $10^{-26}kg$
(d) $10^{-27}kg$

17. The radius of an atomic nucleus in of the order of:

(a) $10^{-10}cm$
(b) $10^{-13}cm$
(c) $10^{-15}cm$
(d) $10^{-8}cm$

18. Which has no unpaired electrons:

(a) $Fe^{+2}$
(b) $Mn^{+2}$
(c) $Cu^{+}$
(d) $Cu^{++}$

19. The fundamental particle responsible for keeping the nucleons together is:

(a) Muon
(b) Meson
(c) Antiproton
(d) Positron

20. Mass number of an element is equal to:

(a) Number of protons
(b) Number of neutrons
(c) Sum of the number of protons and number of neutrons
(d) Sum of the mass of neutrons and mass of protons

21. The atomic weight of an element is due to:

(a) Electrons, neutrons and protons
(b) Neutrons and protons
(c) Electrons and protons
(d) Electrons and neutrons

22. The increasing order (lowest first) for the value of e/m (charge / mass) for:

(a) $e, p, n, \alpha$
(b) $n, p, e, \alpha$
(c) $n, p, \alpha, e$
(d) $n, \alpha, p, e$

23. Cl atom and $Cl^-$ ion differ in the following respect except:

(a) Net electric charge
(b) Number of electrons
(c) Number of protons

24. The no. of $e^-$ by $Na, Na^+$ are respectively:

(a) 11, 11
(b) 10, 11
(c) 11, 10
(d) 10, 10

25. Rutherford’s experiment on scattering of $\alpha$-particles showed for the first time that the atom has:

(a) Electron
(b) Protons
(c) Nucleus
(d) Neutrons

26. Which does not have $18e^-$ here:

(a) Cl
(b) $Cl^-$
(c) $Ca^{+2}$
(d) Ar

27. When alpha particles are sent through a thin metal foil, most of them go straight through the foil because:

(a) Alpha particles are much heavier than electrons
(b) Alpha particles are positively, charged
(c) Most part of the atom is empty space
(d) Alpha particles move with high velocity

28. Rutherford’s alpha particles scattering experiment eventually led to the conclusion that:

(a) Mass and energy are related
(b) Electrons occupy space around the nucleus
(c) Neutrons are deep in the nucleus
(d) The point of impact with matter can be precisely determined

29. Which of the following relates to photons both as wave motion and as a stream of particles?

(a) Interference
(b) $E = mc^2$
(c) Diffraction
(d) E = hv

30. One atom of $^39_19 K$ contains:

(a) 19p, 20n, and 19e
(b) 19p, 20n and 20e
(c) 20p, 19n and 20e
(d) 20p, 19nand 19e

31. The nitride ion in lithium nitride is composed of:

(a) $7p + 7e^-$
(b) $10p + 7e^-$
(c) $7p + 10e^-$
(d) $10p + 10e^-$

32. A transition metal ‘X’ has a configuration $[Ar]3d^4$ in its +3 oxidation state. Its atomic number is:

(a) 25
(b) 26
(c) 22
(d) 19

33. Atomic number is equal to:

(a) Number of neutrons in the nucleus
(b) Number of protons in the nucleus
(c) The sum of number of neutrons and protons
(d) Atomic weight of element

34. The wavelength of light having wave number $4000cm^{-1}$

(a) $1.0 \mu m$
(b) $1.5 \mu m$
(c) $2.0 \mu m$
(d) $1.5 \mu m$

35. The value of Bohr radius of hydrogen atom is:

(a) $0.0529 \times 10^{-6}cm$
(b) $0.0529 \times 10^{-12}cm$
(c) $0.0529 \times 10^{-8}cm$
(d) $0.0529 \times 10^{-10}cm$

36. Experimental evidence for the existence of the atomic nucleus comes from:

(a) Millikan’s oil drops experiment
(b) Atomic emission spectroscopy
(c) The magnetic bending of cathode rays
(d) Alpha scattering by a thin metal foil

37. Which of the following statements does not from part of Bohr’s model of the hydrogen:

(a) Energy of the electrons in the orbit
(b) The electron in the orbit nearest the nucleus is of the lowest energy
(c) Electrons revolve in different orbits around the nucleus
(d) The position and velocity of the electrons in the orbit cannot be determined simultaneously

38. The number of electrons in $[_{19}K^{40}]^-$ is:

(a) 40
(b) 20
(c) 18
(d) 19

39. The general electronic configuration $(n- 1)d^3 n s^2$ indicates that particular element belongs to:

(a) V B
(b) VI B
(c) VII B
(d) III B

40. Atomic mass of an element is 23 and it contains 11 protons. It will consist:

(a) 11p, 23n and 11 e
(b) 11p, 11n and 11e
(c) 11p, 11n and 11e
(d) 11p, 12n and 23e

41. The elements in an atom:

(a) Will move randomly around its nucleus
(b) Will be fixed in space around its nucleus
(c) Will be stationary in various energy levels
(d) Will move around its nucleus in definite energy levels

42. The space between nucleus and electrons in an atom is:

(b) Full of air
(c) Empty
(d) None of the above

43. Bohr model can explain:

(a) The spectrum of hydrogen atom or Hydrogenic species
(b) Spectrum of an atom or ion containing one electron only
(c) The spectrum of hydrogen molecule
(d) The solar spectrum

44. An atom is electrically neutral because:

(a) The nucleus is in the centre of the atom
(b) It contains neutrons
(c) It contains equal number of protons
(d) The electrons are in a state of continuous motion around the nucleus

45. The number of neutrons in dispositive zinc ion with mass number 70 is:

(a) 34
(b) 36
(c) 38
(d) 40

46. An atom which has lost one electron will be:

(a) Electrically neutral
(b) Negatively charged
(d) Positively charged

47. Which of the following subatomic particles are always found in the nuclei of atoms?

(a) Electron
(b) $\alpha$
(c) Positrons
(d) Protons

48. The value of m of an electron is +2.it may be?

(a) 3d
(b) 2p
(c) 3s
(d) 4p

49. Which of the following symbols represents a species containing 10 electrons, 11 protons and 12 neutrons:

(a) $^{21}Ne$
(b) $^{21}Ne+$
(c) $^{21}Na$
(d) $^{21}Na+$

50. Which of the following properties of atoms of elements is the whole number:

(a) Atomic weight
(c) Atomic number
(d) Atomic volume

51. The modern standard for relative mass is:

(a) Carbon isotope with mass number 12
(b) $_1^1H$
(c) Naturally occurring carbon
(d) $^{16}_8$

52. The wavelength of a spectral line for an electronic transition is inversely related to:

(a) The number of electrons undergoing the transition
(b) The nuclear charge of the atom
(c) The difference in the energy of the energy levels involved in the transition
(d) The velocity of the electron undergoing the transition

53. The wave number of the light emitted by a certain source is $2 \times 10^6 m^{-1}$. The wavelength of this light is:

(a) 500 m
(b) 200 nm
(c) 500 nm
(d) $5 \times 10^{7}m$

54. The ratio of the energy of a photon of $2000 \AA$ wavelength radiation to that of $4000 \AA$ radiation is:

(a) 1/4
(b) 4
(c) ½
(d) 2

55. If the wavelength of the first line of the Balmer series of hydrogen atom is $6561 \AA$ the wavelength of the second line of the series should be:

(a) $13122 \AA$
(b) $3280 \AA$
(c) $4860 \AA$
(d) $2187 \AA$

56. Which of the following electron transition in a hydrogen atom will atom will the largest amount of energy:

(a) From n = 1 to n = 2
(b) Form n = 2 to n = 3
(c) Form n = $\infty$ to n = 1
(d) From n = 3 to n = 5

57. The binding energy of the electron in the lowest orbit of the hydrogen atom is 13.6 eV. The energies required in eV to remove an electron form the three lowest orbits of the hydrogen atom are:

(a) 13.6, 6.8, 3.4
(b) 13.6, 10.2, 3.4
(c) 13.6, 27.2, 40.8
(d) 13.6, 3.4, 1.5

58. Consider the spectral line resulting from the transition n = 2 to n = 1 in the atoms and the ions given below. The shortest wavelength is produced by:

(a) Hydrogen atom
(b) Single ionized helium
(c) Deuterium atom
(d) Doubly ionized lithium

59. The ionization potential of hydrogen atom is 13.6 eV. The energy required to remove an electron in the n = 2 state of the hydrogen atom is:

(a) 27.2 eV
(b) 13.6 eV
(c) 6.8 eV
(d) 3.4 eV

60. If each hydrogen atom is excited by giving 8.4 eV of energy, then the number of spectral lines emitted is equal to:

(a) One
(b) Two
(c) Three
(d) Four

61. During electronic transition from higher to lower orbit:

(a) Absorption of energy occurs in integral multiple of a unit
(b) Absorption of energy occurs in a continuous
(c) Emission of energy occurs in integral multiple of a unit
(d) Emission of energy occurs in continuous manner

62. The angular part of the wave function depends on:

(a) l
(b) n
(c) s
(d) both n and l

63. the energy of the electron in nth Bohr’s orbit in the hydrogen atom is given by expression:

(a) $\dfrac{-2 \pi^2 m^4 e^2 Z^2}{n^2h^2}$
(b) $\dfrac{-n^2h^2}{2 \pi^2 Z^2 m e^4}$
(c) $\dfrac{-2 \pi^2 Z^2 e^4 m}{n^2h^2}$
(d) $\dfrac{-2 \pi m^2 e^2 Z^4}{n^2h^2}$

64. For an f electron mvr will be?

(a) $\sqrt{2}\bar{h}$
(b) $\sqrt{12}\bar{h}$
(c) $\sqrt{6}\bar{h}$
(d) Zero

65. The wave number of first line of Balmer series of hydrogen atom is $15200 cm^{-1}$ what is the wave number of first line of Balmer series of $Li^{2+}$ ion?

(a) $15200 cm^{-1}$
(b) $6080 cm^{-1}$
(c) $76000 cm^{-1}$
(d) $136800 cm^{-1}$

66. ‘g’ sub-shell is called:

(a) Spherical
(b) Principle
(c) Degenerated spectrum lines
(d) Fundamental

67. The maximum number of electron are in

(a) 71 g chlorine
(b) 98 g magnesium
(c) 127 g iodine
(d) 4 g hydrogen

68. The binding energy of an electron in the nth orbit of hydrogen atom is:

(a) $13.6 /n^4 eV$
(b) $13.6 /n^4 eV$
(c) $13.6 /n^4 eV$
(d) $13.6 /n^4 eV$

69. Transition of an electron from n = 3 leel to n = 1 leel results in:

(a) Band spectrum
(b) Emission spectrum
(c) Infra red spectrum
(d) X-ray spectrum

70. Line spectrum is the characteristic of:

(a) Atom
(c) Molecule
(d) None of these

71. The number of electrons in the atom which has 20 protons in the nucleus is:

(a) 10
(b) 20
(c) 30
(d) 40

72. The radius of second Bohr’s orbit is:

(a) 0.053 nm
(b) (0.053 / 4)nm
(c) $0.053 \times 2^2$
(d) 0.053 × 20 nm

73. Which of the following relations is not correct:

(a) $E = hc / \lambda$
(b) E = hv
(c) $\lambda = h / mp$
(d) $\lambda = h / mv$

74. The radius hydrogen atom in the ground state is $0.53 \AA$. The radius of $Li^{++}$ ion (atomic number = 3) in similar state is:

(a) $1.06 \AA$
(b) $0.265 \AA$
(c) $0.13 \AA$
(d) $0.53 \AA$

75. The wavelength of an electromagnetic radiation with the energy $2.6 \times 10^{-12}$ erg is:

(a) $8000\AA$
(b) $7600 \AA$
(c) $4000\AA$
(d) $1200\AA$

76. A photon of radiation of wavelength $6000\AA$ has an energy E. the wavelength of photon of radiation that corresponds to an energy equal to 2E is:

(a) $6000\AA$
(b) $3000\AA$
(c) $12000\AA$
(d) $2400\AA$

77. Which one of the following series of lines is found in the U.V. region of atomic spectrum of hydrogen:

(a) Balmer
(b) Paschen
(c) Bracket
(d) Lyman

78. Different lines in Balmer serried of hydrogen atom lie in:

(a) I.R. region
(b) Visible region
(c) U.V. region
(d) Far infra red region

79. Spectrum produced due to transition of an electron form M to L shell is:

(a) Absorption
(b) Emission
(c) X-rays
(d) Continuous

80. An atom has 26 electrons, its atomic weight is 56, the number of neutrons in the nucleus of the atom will be:

(a) 26
(b) 30
(c) 35
(d) 56

81. Which sub-shell is not permitted?

(a) 4 f
(b) 3 g
(c) 4 d
(d) 3 s

82. The ratio of the radii of the first three Bohr orbits is:

(a) 1: 1/2: 1/3
(b) 1 : 2 : 3
(c) 1 :4 : 9
(d) 1 : 8 : 27

83. According to Bohr’s model of an atom, the electrons revolve around the nucleus in:

(a) Orbits
(b) Sub-orbits
(c) Orbitals
(d) Electron cloud

84. The atomic line spectral which usually consist of a few sharp lines are direct measure of the:

(a) Energy changes of the inner electrons of an atom
(b) Energy changes of the outer electrons of an atom
(c) Energy content of an energy level
(d) Number of electrons in an atom

85. Lines in an atomic spectrum are due to:

(a) Energy of electrons
(b) Electrons excited form lower energy levels to higher energy levels
(c) Excited electrons dropping form higher energy levels to lower energy levels
(d) Nuclear charges

86. The photoelectric emission form a surface starts only when the light incident upon the surface has certain minimum:

(a) Frequency
(b) Wavelength
(c) Speed
(d) Intensity

87. The energy of an electron in the third orbit is E3 and that in the second orbit is E2. Then

(a) E2 is equal to E3
(b) E2 is less than E3
(c) E2 is greater than to E3
(d) The sum of E2 and E3 is zero

88. Spectral lines similar to hydrogen atoms are given by:

(a) D, He, LI, Be
(b) $D, He, Li^+, Be^{2+}$
(c) $D, He, Li^{2+}, Be^{2+}$
(d) $D, He^+, Li^{2+}, Be^{3+}$

89. The maximum no of electron when n = 3 is:

(a) 18
(b) 10
(c) 32
(d) 9

90. Bohr’s concept of an orbit in an atom contradicts:

(a) de-Broglie’s relation
(b) Hund’s rule
(c) Pauli’s exclusion principle
(d) Uncertainty principle

91. $Na^+$ ion is isoelectronic with:

(a) $K^+$
(b) $Mg^{++}$
(c) $Ca^{++}$
(d) $Rb^+$

92. Which one statement is wrong?

(a) Mass defect is related with binding energy
(b) Yukawa discovered ‘meson’
(c) Magnetic quantum number in the measurement of “orbital angular momentum”
(d) The radius of the nucleus is of the order $10^{-12}-10^{-13}$

93. Which of the following has the maximum number of unpaired d-electrons?

(a) Zn
(b) $Fe^{++}$
(c) $Ni^{++}$
(d) $Cu^{++}$

94. A 3p-orbital has:

(a) Two non-spherical nodes
(b) One spherical an one non-spherical node
(c) Two spherical nodes
(d) One spherical and two non-spherical nodes

95. The ion that is isoelectronic with CO is:

(a) $CN^-$
(b) $O^+_2$
(c) $O_2$
(d) $N^+_2$

96. The uncertainty in the position of an electron (mass = $9.1 \times 10^{-28}$ g moving with a velocity of $3.0 \times 10^4 cm s^-$ accurate upto 0.011% will be (use $h / 4 \pi$ in uncertainty expression where $h = 6.626 \times 10^{-27}$ erg:

(a) 1.92 cm
(b) 3.84 cm
(c) 5.76 cm
(d) 7.68 cm

97. 4s orbital has how many angular nodes:

(a) 4
(b) 3
(c) 0
(d) 1

98. The size and energy of an electron in the orbital is referred to by:

(a) Principal quantum number
(b) Azimuthal quantum number
(c) Magnetic quantum number
(d) Spin quantum number

99. Magnetic quantum number is related to:

(a) Shape
(b) Size
(c) Orientation
(d) Spin

100. In wave mechanical treatment of the atom, four quantum numbers are assigned. These numbers:

(a) Are arbitrarily given
(b) Express the allowed energy levels of the system
(c) Are useful in calculating the potential energy of the atom
(d) Have no significant value

101. The shape of an sub-orbit is governed by the:

(a) azimuthal quantum number
(b) principal quantum number
(c) magnetic quantum number
(d) spin quantum number

102. when electrons are not present $\Psi^2$ is:

(a) positive
(b) negative
(c) fractional
(d) zero

103. Which one of the following is the electronic configuration of noble gas?

(a) $1s^2, 2s^2, sp^6, 3s^2, 3p^5$
(b) $1s^2, 2s^2, sp^6, 3s^1$
(c) $1s^2, 2s^2, sp^6, 3s^2, 3p^6$
(d) $1s^2, 2s^2, sp^6, 3s^2$

104. The maximum number of electrons in d-sub-shell is:

(a) 2
(b) 8
(c) 32
(d) 10

105. Splitting of spectral line under the influence of magnetic field is called:

(a) Stark effect
(b) Photoelectric effect
(c) Compton effect
(d) Zeeman effect

106. The two electrons in the K-shell will differ in:

(a) Principal quantum number
(b) Azimuthal quantum number
(c) Spin quantum number

107. The preference of three unpaired electrons in the nitrogen atom can be explained by:

(a) Pauli’s exclusion principle
(b) Aufbau principle
(c) Uncertainty principle
(d) Hund’s rule

108. ‘No two electrons can have all the four quantum numbers identical’. This law was given by:

(a) Pauli
(b) Heisenberg
(c) Hund
(d) Schrodinger

109. An atom orbital:

(a) Definite exactly the position of an electron relative to the nucleus
(b) Has a shape dependent on the spin of the electron
(c) Is always spherical in shape
(d) Represents the probability of finding an electron at a certain distance from the nucleus

110. The maximum number of electrons may be present in one d-orbital:

(a) 2
(b) 4
(c) 6
(d) 10

111. Which one of the following diagrams shows a violation of Pauli’s exclusion principle?

(a)$\uparrow \downarrow \, \, \, \uparrow \,\,\, \uparrow \,\,\, \uparrow \,\,\, \uparrow$
(b)$\uparrow \downarrow \, \, \, \uparrow \downarrow \, \, \, \, \uparrow$
(c)$\uparrow \downarrow \, \, \, \uparrow \uparrow \, \, \, \uparrow \, \, \, \uparrow \, \, \, \uparrow$
(d)$\uparrow$

112. Energy of an electron is specified by:

(a) Magnetic quantum number
(b) Principal quantum number
(c) Spin quantum number
(d) Azimuthal quantum number

113. For a particular principal quantum number, the energy will be maximum for the orbital:

(a) p
(b) s
(c) d
(d) f

114. the principal quantum number represents:

(a) distance of electron from nucleus
(b) shape of the orbitals
(c) number of electrons in an orbit
(d) number of orbitals in an orbit

115. Which one of the following is isoester to $CN^-$ ion?

(a) $O^+_2$
(b) Si
(c) CO
(d) $F^-_2$

116. The de Broglie equation treats an electron to be:

(a) A particle
(b) Wave
(c) Both a particle and a wave
(d) None of these

117. The element of atomic number 29 has the following electronic configuration:

(a) $[Ar]4s^2 4p^3$
(b) $[Ar]4d^{10} 4s^1$
(c) $[Ar]4d^9 4s^1$
(d) $[Ar]4s^2 4p^6$

118. The total possible values for magnetic quantum number for the value of l = 3 is:

(a) 3
(b) 1
(c) 5
(d) 7

119. Energy of atomic orbitals in a particular shell is in the order:

(a) s < p < d < f
(b) s > p > d > f
(c) p < d < f < s
(d) f > d > s > f

120. for azimuthal quantum number l = 3 the maximum number of electrons will be:

(a) 10
(b) 2
(c) 12
(d) 6

121. A neutral atom (atomic No. > 1) consists of:

(a) Neutrons + electrons
(b) Neutrons + protons
(c) Only protons
(d) Neutrons + electrons + protons

122. The principle which gives a way to fill the electrons in the available energy level is:

(a) Hund’s rule
(b) Pauli’s exclusion principle
(c) Aufbau principle
(d) None of these

123. Aufbau principle is not correct for

(a) Cu and Ar
(b) Cu and Cr
(c) Cr and Ar
(d) Fe and Ag

124. Simultaneous determination of both position and momentum of an electron is not possible. The principle was given by:

(a) Heisenberg
(b) Clark Maxwell
(c) De Broglie
(d) Davisson and Germer

125. Aufbau principle is obeyed in which of the following electronic configurations:

(a) $1s^2 3s^2 3p^6$
(b) $1s^2 2s^2 2p^6$
(c) $1s^2 2s^2 3s^2$
(d) None of these

126. The orbitals are called degenerate when:

(a) They have same wave functions but different energy
(b) They have different wave functions but same energy
(c) They have the same energy
(d) They have the same wave function

127. For a given value of azimuthal quantum number l, the values for the magnetic quantum number m, are given by:

(a) l + 1
(b) 2l + 1
(c) L + 2
(d) 2l + 2

128. Which one of the following contains only an electron and a proton:

(a) Helium
(b) Deuterium
(c) Tritium
(d) Hydrogen

129. What are the possible values of azimuthal quantum number (l) for an electron with the principal quantum number, n = 4:

(a) 0, 1 and 2
(b) 1, 2 and 3
(c) 2, 3 and 4
(d) 0, 1, 2 and 3

130. Which neutral atom has 18 electrons in its outer shell:

(a) $Cu^+$
(b) Fe
(c) $Mn^{+2}$
(d) Zn

131. A cricket ball of 0.5 kg is moving with a velocity of $m s ^{-1}$. The wavelength associated with its motion is:

(a) 1 / 100 cm
(b) $6.6 \times 10^{-34} m$
(c) $1.32 \times 10^{-35}$
(d) $6.6 \times 10^{-28}$

132. De Broglie equation is:

(a) $E = mc^2$
(b) $c = \lambda v$
(c) $h /mv =\lambda$
(d) $hv = hv = E_1- E_2$

133. A 200 g ball is thrown with a velocity $30 m s^{-1}$. The de Broglie wavelength is to be:

(a) $10^{-32} m$
(b) $10^{-34} m$
(c) $10^{-36} m$
(d) $10^{-38} m$

134. The de Broglie wavelength of $10^{-17} m$by momentum of a particle will be:

(a) $13.25 \times 10^{-17} kg m s^{-1}$
(b) $26.5 \times 10^{-7} kg m s^{-1}$
(c) $6.625 \times 10^{-11} kg m s^{-1}$
(d) $3.3625 \times 10^{-7} kg m s^{-1}$

135. The unpaired electrons in $Mn^{++}$ ion are:

(a) 1
(b) 5
(c) 3
(d) 4

136. An atom of Cr (atomic number 24) has one 4s electron and five 3d electrons. How many unpaired electrons would be there in $Cr^{2+}$ ?

(a) 4
(b) 3
(c) 2
(d) 1

137. The number of unpaired electrons in $Cr^{3+}$ ion is:

(a) 6
(b) 4
(c) 3
(d) 1

138. The number of nodal planes in a px orbital is:

(a) Two
(b) One
(c) Three
(d) Zero

139. The electronic configuration of an element is $1s^2 2s^2 3s^2 3p^3$. What is the atomic number of the element which is just below the above element in the periodic table?

(a) 33
(b) 34
(c) 31
(d) 49

140. When 4p orbitals in any atom are filled completely the new electron goes in:

(a) 5s
(b) 3d
(c) 4d
(d) 4f

141. Which orbital is not possible or does not exit:

(a) 1p
(b) 2d
(c) 3f
(d) All of these

142. Number of unpaired electrons in the electronic configuration $1s^2 2s^2 2p^4$ is:

(a) 2
(b) 3
(c) 4
(d) 6

143. The electronic configuration of an element is $1s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^1$. This represents its:

(a) Excited state
(b) Ground state
(c) Cationic state
(d) Anionic state

144. There is filled or half filled set of p – or d-orbital spherically symmetric. Point out the species which has spherically symmetric:

(a) C
(b) $Cl^-$
(c) Fe
(d) Na

145. If the value of l is 2, what will be the value of principal quantum number?

(a) 0
(b) 3
(c) 2
(d) 1

146. The filling of the 4p orbital begins in the element of atomic number:

(a) 19
(b) 29
(c) 31
(d) 35

147. $\Psi_{4, 0, 0}$ represents which orbital?

(a) 3p
(b) 4s
(c) 3d
(d) 4p

148. The orbital diagram in which the Aufbau principle is isolated is:

2s 2p
(a)$\uparrow \downarrow \, \, \, \, \uparrow \downarrow \, \, \, \uparrow$
(b) $\uparrow \, \, \, \, \uparrow \downarrow \, \, \, \uparrow \, \, \, \uparrow$
(c) $\uparrow \downarrow \, \, \, \, \uparrow \, \, \, \uparrow \, \, \, \uparrow$
(d) $\uparrow \downarrow \, \, \, \, \uparrow \downarrow \, \, \, \uparrow \downarrow \, \, \, \uparrow$

149. The outermost electronic configuration of the most electronegative element is:

(a) $ns^2 np^3$
(b) $ns^2 np^4$
(c) $ns^2 np^5$
(d) $ns^2 np^6$

150. If $\alpha$-particle is bombarded on gold foil, then:

(a) Most of the $\alpha$-particles are deflected
(b) Some $\alpha$-particles are deflected
(c) Maximum $\alpha$-particles are deflected
(d) All $\alpha$-particles return to original path

151. For n = 3 energy level the no. of possible orbitals of all kind are:

(a) 1
(b) 3
(c) 4
(d) 9

152. 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) 1s

153. Correct set of four quantum numbers for the valence (outer most) electron of rubidium (Z = 37) is:

(a) 5, 0, 0, +1/2
(b) 5, 1, 0, +1/2
(c) 5, 1, 1, +1/2
(d) 6, 0, 0, +1/2

154. The correct ground state electronic configuration of chromium atom is:

(a) $[Ar] 3d^5 4s^1$
(b) $[Ar] 3d^4 4s^2$
(c) $[Ar] 3d^5 4s^0$
(d) $[Ar] 4d^5 4s^1$

155. Which one of the following orbital is dumbbell shape:

(a) s
(b) d
(c) p
(d) f

156. the number of unpaired electrons in ferrous ion is:

(a) 2
(b) 3
(c) 4
(d) 5

157. The quantum number values for the designation 3d are:

(a) n = 3, m = -3
(b) n = 3, m = 3
(c) n = 4, m = 1
(d) n = 3, m = 2

158. the order of quantum numbers not applicable for an electron in an atom is:

(a) 3d, 4s, 4p, 4d, 5s
(b) 4s, 3d, 4p, 5s, 4d
(c) 5s, 4p, 3d, 4d, 5s
(d) 3d, 4p, 4s, 4d, 5s

159. The set of quantum numbers not applicable for an electron in an atom is:

(a) $n = 1, l = 1, m_1 = 1, m_s = +1/2$
(b) $n = 1, l = 0, m_1 = 0, m_s = +1/2$
(c) $n = 1, l = 0, m_1 = 1, m_s = +1/2$
(d) $n =21, l = 0, m_1 = 0, m_s = +1/2$

160. The correct set of quantum number (n, l, m) to signify $3p_z$ orbit is:

(a) $n = 3, l = 1, m = -1$
(b) $n = 3, l = 0, m = 0$
(c) $n = 3, l = 2, m = 1$
(d) $n = 2, l = 1, m = -2$

161. Which of the following represents the correct sets of the four quantum numbers of a 4d electron?

(a) 4, 3, 2, +1/2
(b) 4, 2, 1, 0
(c) 4, 3, -2, +1/2
(d) 4, 2, 1, -1/2

162. The correct order of decreasing stability of different orbitals is:

(a) $3d^5 > 3d^6 > 1s^2 > 4d^{10} > 2p^3$
(b) $3d^6 > 2p^3 > 4ds^{10} > 1s^2 > 3d^5$
(c) $3d^6 > 3d^5 > 2p^3 > 4d^{10} > 1s^2$
(d) $1s^2 > 4d^{10} > 2p^3 > 3d^5 > 3d^6$

163. The electronic configuration $1s^2 2s^2 2p^6 3s^1 3p^1$ represents:

(a) Ground state of Na
(b) Ground state if $Si^{++}$
(c) Exited state of Mg
(d) Excited state of $Al^{++}$

164. Which one of the following set of quantum numbers of an electron in any atom is not corresponding to wave equation:

n l m s
(a) 3 2 -2 1/2
(b) 3 3 1 -1/2
(c) 3 2 1 1/2
(d) 3 1 1 -1/2

165. Which of the following sets of quantum numbers (listed in order of n, l, m, s) are impossible for an electron in an atom?

(a) 4, 2, 0, +1/2
(b) 3, 3, -3, -1/2
(c) 2, 0, 1, +1/2
(d) 4, 3, 0, +1/2

166. The number of d-electrons in $Fe^{2+}$ (atomic number if Fe = 26) is not equal to that of the:

(a) p-electrons in Ne(atomic number = 10)
(b) s-electrons in Mg (atomic number = 12
(c) d-electrons in Fe
(d) p-electrons in $Cl^-$ (atomic number = 17)

167. which of the following sets of quantum numbers is not permitted:

n l m s
(a) 4 1 0 1/2
(b) 1 1 0 1/2
(c) 3 2 -2 1/2
(d) 1 0 0 ½

168. If n = 3 and l = 2 the orbital may be:

(a) 3d
(b) 4p
(c) 3p
(d) 4s

169. The first use of quantum theory to explain the structure of atom was made by:

(a) Heisenberg
(b) Bohr
(c) Planck
(d) Einstein

170. What is the correct designation for an electron with the quantum numbers, n = 3, l = 1 and m = 0:

(a) 3d
(b) 3p
(c) 3s
(d) 4s

171. For a ‘d’ electron, the orbital angular momentum is:

(a) $\bar{h}$
(b) $\sqrt{2}\bar{h}$
(c) $\sqrt{6}\bar{h}$
(d) $2\bar{h}$

172. The correct set of quantum numbers for the unpaired electron of chlorine atom is::

n l m
(a) 2 1 0
(b) 2 1 1
(c) 3 1 1
(d) 3 0 0

173. Indicate which electronic configuration amongst the following correctly represents the sulphur atom:

(a) $1s^2 2s^2 2p^6 3s^2 3p^2 3d^2$
(b) $1s^2 2s^2 2p^6 3s^2 3p^2 4s^2$
(c) $1s^2 2s^2 2p^6 3s^2 3p^2 4s^1 4p^1$
(d) $1s^2 2s^2 2p^6 3s^2 3p^4$

174. Which of the following sets of quantum number belongs to highest energy:

n l m s
(a) 3 1 1 +1/2
(b) 3 0 0 +1/2
(c) 4 0 0 +1/2
(d) 3 2 1 +1/2

175. Which orbit will be first to have a ‘g’ sub-shell?

(a) L
(b) M
(c) N
(d) O

176. The magnetic quantum number for valence electron of sodium is:

(a) 3
(b) 2
(c) 1
(d) 0

177. The atomic number of nitrogen is 7 and that of oxygen is 8. The toyal number of electrons in a nitrate ion will be:

(a) 8
(b) 16
(c) 32
(d) 64

178. The uncertainty in position of an electron is zero. The uncertainty in its movement would be:

(a) Zero
(b) $> h / 2 \pi$
(c) $< h / 2 \pi$
(d) Infinity

179. According to uncertainty principle:

(a) $E = mc^2$
(b) $\Delta x \times \Delta p = h / 4 \pi$
(c) $\lambda = h / 2 \pi$
(d) $\Delta x \times \Delta p = h / 6 \pi$

180. If electron falls from n = 3 to n = 2, in hydrogen atom then the emitted energy is:

(a) 10.2 eV
(b) 12.9 eV
(c) 1.9 eV
(d) 0.9 eV

181. A completely filled ‘d’ orbit $(d^{10})$ is:

(a) Spherically symmetric
(b) Symmetrically octahedral
(c) Symmetrically tetrahedral
(d) Depends on the atom

182. The total number of electrons that can be accommodated in all the orbitals having principle quantum number 2 and azimuthal quantum number 1 is:

(a) 2
(b) 4
(c) 6
(d) 8

183. Electronic configuration of calcium atom may be written as:

(a) $(Ne) 3p^2$
(b) $(Ar) 4s^2$
(c) $(Ne) 4s^2$
(d) $(Kr)4p^2$

184. Angular momentum of an electron revolving around a nucleus is an integral multiple of:

(a) $h / 2 \pi$
(b) h
(c) h / 2
(d) 2h

185. The maximum number of electrons that can be accommodated in a quantum shell is :

(a) n
(b) $n^2$
(c) $2n^2$
(d) n(n + 1)

186. an orbital with l = 0 is:

(b) symmetrical about the x-axis only
(c) symmetrical about the y-axis only
(d) symmetrical about the z-axis only

187. Which of the following elements possesses maximum number of unpaired electrons?

(a) B
(b) C
(c) N
(d) O

188. How many orbits are present in a g sub-shell

(a) 3
(b) 10
(c) 14
(d) 9

189. The total number of electrons present in the first twenty elements of the periodic table is:

(a) 190
(b) 210
(c) 230
(d) 250

190. Which of the following electronic configurations is against the Pauli’s exclusion principle?

(a) $1s^2 2s^2 2p^6$
(b) $1s^2 2s^2 2p^6 3s^1$
(c) $1s^2 2s^2 2p^6 3s^2$
(d) $1s^2 2s^2 2p^6 3s^3$

191. Pauli law decides max. number of electrons in:

(a) Orbits only
(b) Orbit, sub-orbit
(c) Orbit, sub-orbit, orbital
(d) Has no concern to decide number of electrons

192. Which of the following orbitals is symmetrical about x-axis:

(a) $p_x$
(b) $p_y$
(c) $p_z$
(d) $d_{x^2- y^2}$

193. Which of the following electrons will not be found in XY-plane?

(a) $p_x$
(b) $p_y$
(c) $p_z$
(d) $p_{xy}$

194. Which of the following electronic configurations is in excited state:

(a) $1s^2 2s^2$
(b) $1s^2 2p^1$
(c) $1s^2 2s^2 2p^3$
(d) $1s^2 2s^2 2p^6$

195. In an atom there are 2, 8, 11 and 2 electrons in K, L, M and N energy levels respectively. In this atom total number of electrons wills l = 2 will be.

(a) 2
(b) 3
(c) 4
(d) 5

196. The values of n, l, m for the last d-orbital electron of Fe-atom is?

n l m
(a) 4 0 0
(b) 3 2 +2 or -2
(c) 3 2 -1
(d) 3 2 0

197. The de Broglie wavelength of a particle with mass 1.0 g and velocity $100 ms ^{-1}$ is:

(a) $6.63 \times 10^{-35} m$
(b) $6.63 \times 10^{-34} m$
(c) $6.63 \times 10^{-33} m$
(d) $6.63 \times 10^{-32} m$

198. The electronic configuration of the element which is just above the element with atomic number 43 in the same periodic group is:

(a) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^2$
(b) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^5$
(c) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^6 4s^1$
(d) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^{10} 4s^2 4p^6$

199. The number of d-electrons in $[Cr(H_2O)_6]^{3+}$ ion (At. No. of Cr = 24) is:

(a) 2
(b) 3
(c) 4
(d) 5

200. Krypton $(_{36}Kr)$ has the electronic configuration (Ar) $4s^2 3d^{10} 4p^6$. The 37th electron will go into which of the following sub-orbit?

(a) 4f
(b) 3d
(c) 3p
(d) 5s

201. Which one of the following sets of quantum number is wrong:

(a) 3, 1, 0, -1/2
(b) 3, 2, 1, +1/2
(c) 3, 1, 2, -1/2
(d) 3, 2, 0, +1/2

202. Electronic configuration of species $M^{2+}$ is $1s^2 2s^2 2p^6 3s^2 3p^6 3d^6$ and its atomic mass is 56. The number of neutrons in the nucleus of species M is:

(a) 24
(b) 26
(c) 28
(d) 30

203. Which is not paramagnetic in nature:

(a) $Mn^{+2}$
(b) $Cu^{+2}$
(c) $Co^{+3}$
(d) $Cu^{+2} \, \, and \, \, zn^{+2}$

204. Which of the following corresponds to the electronic configuration $1s^2 2s^2 2p^6 3s^2$:

(a) Argon
(b) Sodium
(c) Magnesium
(d) Calcium

205. Which of the following statements is not correct for an electron that has the quantum numbers n = 4 and m = 2?

(a) The electron may have the quantum number s = +1/2
(b) The electron may have the quantum number l = 2
(c) The electron may have the quantum number l = 3
(d) The electron may have the quantum number l = 0, 1, 2, 3

206. The de-Broglie wavelength with a particle of mass 1 mg moving with a velocity of $10 m s^{-1}[$ is:

(a) $6.63 \times 10^{-29}m$
(b) $6.63 \times 10^{-31}m$
(c) $6.63 \times 10^{-34}m$
(d) $6.63 \times 10^{-22}m$

207. According to Bohr’s theory of hydrogen atom, which of the following is for a n electron:

(a) Angular acceleration
(b) Angular momentum
(c) Acceleration
(d) Velocity

208. In a Bohr’s model of atom when an electron jumps from n = 1 to n = 3, how much energy will be emitted or absorbed?

(a) $2.15 \times 10^{-11}erg$
(b) $0.1911 \times 10^{-10}erg$
(c) $2.389 \times 10^{-12}erg$
(d) $2.239 \times 10^{-10}erg$

209. Hund’s rule states that:

(a) Matter and radiation have a dual nature
(b) In an atom no two electrons can have the same set of four quantum numbers
(c) The position and velocity of an electron can not be exactly measured at one and the same time
(d) In orbitals of equilateral energy, electron spins remain unpaired until each orbital holds at least one electron

210. Which orbital will not emit the electron by the absorption of photon?

(a) 1s
(b) 2s
(c) 2p
(d) 3p

211. The mass number of an element possessing 18 electrons and 20 neutrons is:

(a) 20
(b) 18
(c) 38
(d) 2

212. The charge on an electron is $4.8 \times 10^{-10}$ e.s.u. the charge on the nucleus of $Li^+$ ion is:

(a) $4.8 \times 10^{-10} e.s.u$
(b) $9.6 \times 10^{-10} e.s.u$
(c) $1.44 \times 10^{-9} e.s.u$
(d) $1.44 \times 10^{9} e.s.u$

213. The radius of first orbit is $a_0$ for an atom. The radius of third orbit of the same atom will be:

(a) $3 \times a_0$
(b) $6 \times a_0$
(c) $9 \times a_0$
(d) $\dfrac{1}{9} \times a_0$

214. For an electron, principal quantum number is 3. Its number of sub-orbits and orbitals will be:

(a) 3 and 5
(b) 3 and 7
(c) 3 and 9
(d) 2 and 5

215. The uncertainty principle and wave nature of matter are proposed by ………………… and ………… respectively.

(a) Heisenberg and de Broglie
(b) Heisenberg and Pauli
(c) De Broglie and Heisenberg
(d) Planck and Einstein

216. The following ions/atoms have five electrons in the outermost orbit, the one which has not the value of azimuthal quantum number equals to 2 is:

(a) P(0)
(b) Fe (III)
(c) Cr (III)
(d) Mn (II)

217. The configuration $1s^2 2s^2 2p^5 3s^1$ shows:

(a) Ground state of fluorine atom
(b) Excited state of fluorine atom
(c) Excited state of neon atom
(d) Excited state of ion $O_2^-$

218. The electronic configuration of an element C is $1s^2 2s^2 2p^6$. The substance in which only C will be, has formula:

(a) C
(b) $C_2$
(c) $C_4$
(d) $C_6$

219. The electronic configuration of $_{21}Sc$ is:

(a) $1s^2 2s^22p^6 3s^2 3p^6 4s^2 3d^1$
(b) $1s^2 2s^22p^6 3s^2 3p^6 3d^3$
(c) $1s^2 2s^22p^6 3s^2 3p^6 4s^1 3d^2$
(d) $1s^2 2s^22p^6 3s^2 3p^6 4s^2 3d^2$

220. The energy of a photon is:

(a) Directly proportional to its velocity
(b) Inversely proportional to the wavelength
(c) Directly proportional to frequency
(d) Directly proportional to its wavelength

221. An electronic transition from its orbital of an atom causes:

(a) Absorption of energy
(b) Release of energy
(c) Both release and absorption of energy
(d) Unpredictable

222. Which orbital does not have any nodal plane:

(a) p
(b) s
(c) d
(d) f

223. the energy of an electron in the first Bohr orbit of H atom is -13.6 eV. The possible energy value (s) of the excited state (s) for electrons in Bohr’s orbits of hydrogen is (are):

(a) -3.4 eV
(b) -4.2 eV
(c) -6.8 eV
(d) +6.8 eV

224. Which of the following statement (s) is (are) correct?

(a) The electronic configuration of Cr is $(Ar)3d^5 4s^1$ (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. (atomic No. of Ag = 47)
(d) The oxidation state of nitrogen in $HN_3$ is -3
(e) a, b, c

225. the uncertainty in the momentum of an electron is $1 \times 10^{-5} kg m s^{-1}$. The uncertainty in its position will be $( h = 6.62 \times 10^{-34} kg m^2 s^{-1})$

(a) $1.05 \times 10^{-28} m$
(b) $1.05 \times 10^{-29} m$
(c) $5.27 \times 10^{-30} m$
(d) $5.25 \times 10^{-28} m$

226. The Bohr’s orbit radius for the hydrogen atom (n = 1) is approximately $0.530 \AA$ . the radius for the first excited state (n = 2) orbit is ( in $\AA$ ):

(a) 0.13
(b) 1.06
(c) 4.77
(d) 2.12

227. The position of both an electron and a helium atom is known within 1.0nm. further, the momentum of the electron is known within $5.0 \times 10^{-26} kg m^{-1}$. The minimum uncertainty in the measurement of the momentum of the helium is:

(a) $50kg m^{-1}$
(b) $80 kg m^{-1}$
(c) $80 \times 10^{-26} kg m^{-1}$
(d) $5.0 \times 10^{-26} kg m^{-1}$

228. Which of the following is the main cause of late discovery of neutron?

(a) Neutron is chargeless particle
(b) Neutron is highly unstable particle
(c) Neutron in nucleus moves very fast
(d) All of these

229. Plank’s constant has the same dimension as that of:

(a) Power
(b) Work
(d) Angular momentum

230. Who modified Bohr’s theory by introducing elliptical orbits for electron path:

(a) Hund
(b) Thomson
(c) Rutherford
(d) Sommerfeld

231. The expression of Bohr’s radius of an atom:

(a) $r = \dfrac{n^2h^2}{4 \pi^2 m e^4 Z^2}$
(b) $r = \dfrac{n^2h^2}{4 \pi^2 m e^2 Z^2}$
(c) $r = \dfrac{n^2h^2}{4 \pi^2 m e^2 Z^2}$
(d) $r = \dfrac{n^2h^2}{4 \pi^2 m^2 e^2 Z^2}$

232. The ratio of radius of second and third orbit in hydrogen atom is:

(a) 3 : 2
(b) 2 : 3
(c) 4 : 9
(d) 9 : 4

233. To bring electron form infinity towards nucleus their energy increases:

(a) Towards more positive value
(b) Towards less positive value
(c) Towards more negative value
(d) Towards less negative value

234. Brackett series is produced when electrons from the outer orbit jump to:

(a) 2nd orbit
(b) 3rd orbit
(c) 4th orbit
(d) 5th orbit

235. The mass number of an anion $X^{-3}$ is 14. If there are 10 electrons in the anion, the number of neutrons in the nucleus of atom X2 of the element will be:

(a) 10
(b) 14
(c) 7
(d) 5

236. Which of the following is the correct electronic configuration of $Fe^{3+}$ ion?

(a) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^4 4s^1$
(b) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^3 4s21$
(c) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^5$
(d) $1s^2 2s^2 2p^6 3s^2 3p^6 3s^3 3p^3$

237. The correct electronic configuration of Ti (Z = 22) atom is:

(a) $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^2$
(b) $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 4p^2$
(c) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^4$
(d) $1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^3$

238. Which of the following has more unpaired d-electrons:

(a) $Zn^{++}$
(b) $Co^{++}$
(c) $Fe^{++}$
(d) $Mn^{3+}$

239. How many electrons will be in an orbit for which l = 2 cand n = 3?

(a) 2
(b) 6
(c) 14
(d) 10

240. How many orbitals are required for the electronic configuration of ion?

(a) 6
(b) 12
(c) 14
(d) 15

241. Which of the following electronic configurations is correct according to Hund’s rule:

(a) $\uparrow \downarrow \, \, \, \, \uparrow \downarrow \, \, \, \uparrow$
(b) $\uparrow \downarrow \, \, \, \, \uparrow \, \, \, \uparrow \, \, \, \uparrow$
(c) $\uparrow \, \, \, \, \uparrow \downarrow \, \, \, \uparrow \downarrow$
(d) $\uparrow \downarrow \, \, \, \, \uparrow \, \, \, \uparrow \, \, \, \downarrow$

242. Ground state electronic configuration of nitrogen atom can be represented by:

(a)$\uparrow \downarrow \, \, \, \, \ uparrow \downarrow \, \, \, \uparrow \uparrow \, \, \, \uparrow$
(b) $\uparrow \, \, \, \, \uparrow \downarrow \, \, \, \uparrow \downarrow \, \, \, \uparrow \, \, \, \downarrow \, \, \, \uparrow$
(c) $\uparrow \downarrow \, \, \, \, \uparrow \downarrow\, \, \, \uparrow \, \, \, \downarrow \, \, \, \downarrow$
(d) $\uparrow \downarrow \, \, \, \, \uparrow \downarrow \, \, \, \, \downarrow \, \, \, \downarrow \, \, \, \downarrow$
(e) a, \, \, d \, \, both[/latex]

243. For Na (Z = 11) atom, the four quantum numbers of last electron are:

n l m s
(a) 3 1 1 +1/2
(b) 3 0 0 +1/2
(c) 3 0 1 +1/2
(d) 3 1 1 +-1/2

244. Which one of the following quantum number values is not possible for d-orbitals?

n l m s
(a) 3 +2 -3 +1/2
(b) 4 +3 -2 -1/2
(c) 3 +2 0 +1/2
(d) 4 +3 1 -1/2

245. Which of the following configurations is correct for iron?

(a) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^8$
(b) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^7 4s^1$
(c) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^6 4s^2$
(d) $1s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^3$

246. Which of the following explains the sequence of filling the electrons in different shells?

(a) Hund’s rule
(b) Octet rule
(c) Aufbau principle
(d) All of these

247. The electrons identified by quantum number n and l(i) n = 4, l = 1 (ii) n = 4, l = 0 (iii) n = 3, l = 1 can be placed in order of increasing energy form the lowest to highest as:

(a) (iv) < (ii) < (iii) < (i)
(b) (ii) < (iv) < (i) < (iii)
(c) (i) < (iii) < (ii) < (iv)
(d) (iii) < (i) < (iv) < (ii)

248. In a given atom no two electrons can have the same value of all the quantum numbers. This is called:

(a) Hund’s rule
(b) Aufbau principle
(c) Uncertainty principle
(d) Pauli’s exclusion principle

249. Which of the following expressions gives the de Broglie’s relationship:

(a) $\lambda = h /mp$
(b) $\lambda = h mv$
(c) $\lambda = h /mv$
(d) $\lambda = h mp$

250. If wavelength of photon is $2.2 \times 10^{-11}m , \, \, h = 6.6 \times 10^{-34} Js$, then momentum of photon is:

(a) $3 \times 10^{-23} kg m s^{-1}$
(b) $3.33 \times 10^{22} kg m s^{-1}$
(c) $1.452 \times 10^{-44} kg m s^{-1}$
(d) $6.89 \times 10^{43} kg m s^{-1}$

251. Which one of the following forms a colourless solution in aqueous medium?

(a) $V^{3+}$
(b) $Cr^{3+}$
(c) $Ti^{3+}$
(d) $Sc^{3+}$
(Atomic number Sc = 21, Ti = 22, v = 23, Cr = 24)

252. Energy of a photon is given as: $\Delta E / atom = 3.03 \times 10^{-19} J atom^{-1}$ then, the wavelength of the photon is:

(a) 6.56 nm
(b) 65.6 nm
(c) 656 nm
(d) 0.656 nm
Given, h (Plank’s constant) =$6.63 \times 10^{-34} J-sc (velocity of light ) = 3.00 \times 10^8 m s^{-1}$

253. The following quantum numbers are possible for how many orbitals n = 3, l = 2, m = +2:

(a) 1
(b) 2
(c) 3
(d) 4

254. In hydrogen atom, energy of first excited state is -3.4 eV. Then kinetic energy of same orbit of hydrogen atom:

(a) +3.4 eV
(b) +6.8 eV
(c) -13.6 eV
(d) +13.6 eV

255. The value of Planck’s constant is $6.63 \times 10^{-34} J s$. The velocity of light is $3.0 \times 10^8 m s^{-1}$ which value is closest to the wavelength in nanometers of a quantum of light with frequency of $8 \times 10^5 s^{-1}$

(a) $4 \times 10^1$
(b) $3 \times 10^7$
(c) $2 \times 10^{-25}$
(d) $5 \times 10^{-18}$

256. The frequency of radiation emitted when the electron falls from n = 4 to n = 1 in a hydrogen atom will be (given ionization energy of $H = 2.18 \times 10^{-18} J atom ^{-1} and h = 6.625 \times 10{^-34}J s$

(a) $1.54 \times 10^{15} s^{-1}$
(b) $1.03 \times 10^{15} s^{-1}$
(c) $3.08 \times 10^{15} s^{-1}$
(d) $2.00 \times 10^{15} s^{-1}$

257. Among the following series of transition metal ions, the one where all metal ions have 3d2 electronic configuration is:

(a) $Ti^{3+}, V^{2+}, Cr^{3+}, Mn^{4+}$
(b) $Ti^{+}, V^{4+}, Cr^{6+}, Mn^{7+}$
(c) $Ti^{4+}, V^{3+}, Cr^{2+}, Mn^{3+}$
(d) $Ti^{2+}, V^{3+}, Cr^{4+}, Mn^{5+}$
At. Wt. Ti = 22, V = 23, Cr = 24, Mn = 25

258. The de-Broglie wavelength of the electron in the ground state of hydrogen atom is: (K.E. = 13.6 eV ) ; $1 eV = 1.602 \times 10^{-19} J$

(a) 33.28 nm
(b) 3.328 nm
(c) 0.3328 nm
(d) 0.0332 nm

259. The outer –most configuration of most electronegative element is:

(a) $n s^2 np^5$
(b) $n s^2 np^6$
(c) $n s^2 np^4$
(d) $n s^2 np^7$

260. The de-Broglie wavelength associated with a particle of mass $10^{-6 kg}$ moving with a velocity of $10 m s^{-1}$ is:

(a) $6.63 \times 10^{-7} m$
(b) $6.63 \times 10^{-16} m$
(c) $6.63 \times 10^{-21} m$
(d) $6.63 \times 10^{-29} m$

261. The velocity of electron in second shell of hydrogen atom is:

(a) $10.94 \times 10^6 m s^{-1}$
(b) $18.88 \times 10^6 m s^{-1}$
(c) $1.888 \times 10^6 m s^{-1}$
(d) $1.094 \times 10^6 m s^{-1}$

262. Quantum number of an atom can be defined on the basis of:

(a) Aufbau’s principle
(b) Heisenberg’s uncertainty principle
(c) Hund’s rule
(d) Pauli’s exclusion principle

263. The quantum number ‘m’ of a free gaseous atom is associated with:

(a) The effective volume of the orbital
(b) The shape of the orbital
(c) The spatial orientation of the orbital
(d) The energy of the orbital in the absence a magnetic field

264. Which of the following is not possible?

(a) n = 2, l = 1, m = 0
(b) n = 2, l = 0 m = -1
(c) n = 3, l = 0, m = 0
(d) n = 3, l = 1, m = -1

265. the energy ratio of a photon of wavelength $3000 \AA \, \, and \, \, 6000 \AA$ is:

(a) 1 : 1
(b) 2 : 1
(c) 1 : 2
(d) 1 : 4

266. Chromium is represented by the electronic configuration:

(a) $[Ne] 3s^2 3p^6 3d^4 4s^2$
(b) $[Ne] 3s^2 3p^6 3d^2 4s^1$
(c) $[Ne] 3s^2 3p^6 3d^5 4s^1$
(d) $[Ne] 3s^2 3p^6 4s^2 3d^4$

267. Millikan’s oil drop method is used to determine:

(a) Velocity electron
(b) Mass of electron
(c) Charge of electron
(d) e/m ratio of electron

268. wavelength of spectral line emitted inversely proportional to:

(a) energy
(b) velocity
(d) quantum number

269. To explain the structure of atom the first use of quantum theory was made by:

(a) Heisenberg
(b) Bohr
(c) Planck
(d) Einstein

270. The correct set of quantum numbers is:

(a) n = 2, l = 1, m = 0, s = 0
(b) n = 2, l =-2, m = 1, s = +1/2
(c) n = 2, l = 2, m = -1 s = -1/2
(d) n = 2, l = 1, m = 0, s = +1/2

271. the incorrect configuration is:

(a) $K = (Ar) 4s^1$
(b) $Cr = (Ar) 3d^5, 4s^1$
(c) $Cr = (Ar) 3d^4, 4s^1$
(d) $Cr = (Ar) 3d^{10}4s^1$

272. Number of orbitals in L energy level:

(a) 1
(b) 2
(c) 3
(d) 4

273. Ratio of radii of second and first Bohr orbits of H atom is:

(a) 2
(b) 6
(c) 3
(d) 4

274. Dual nature of particle was gives by:

(a) Bohr’s theory
(b) Thomson model
(c) Heisenberg principle
(d) de-Broglie equation

275. l = 3, then the values of magnetic quantum numbers are:

(a) $\pm 1, \pm 2, \pm 3$
(b) $0 \pm 1, \pm 2, \pm 3$
(c) -1, -2, -3
(d) 0, +1, +2, +3

276. Which of the following do not travel with speed of light?

(a) De Broglie waves
(b) X-rays
(c) Gamma rays
(d) All of these

277. How many electrons can be accommodated in a p-orbital?

(a) 6 electrons
(b) 2 electrons
(c) 4 electrons
(d) None of these

278. The atomic number of an element is 17. The number of orbitals electron pairs in its valence shell is:

(a) 3
(b) 4
(c) 6
(d) 8

279. The correct one for d-orbitals is:

(a) $(n-1)d^{1- 9} n s^1$
(b) $(n-1)d^{1- 10} n s^{1- 2}$
(c) $(n-1)d^{1- 5}$
(d) $(n-1)d^{1- 10} n s^2$

280. The radius of hydrogen atom is $0.53 \AA$. The radius of $Li^{2+}$ is of:

(a) $1.27 \AA$
(b) $0.17 \AA$
(c) $0.57 \AA$
(d) $0.99 \AA$

281. The number of nodel planes in a px orbital is:

(a) 1
(b) 2
(c) 3
(d) 0

282. The electronic configuration of an element is $1s^1 2s^2 2p^6 3s^2 3p^6 3d^5 4s^1$. This represents

(a) Excited state
(b) Ground state
(c) Cationic form
(d) Anionic form

283. The quantum numbers +1/2 and -1/2 for the electron spin represent:

(a) Rotation of the electron in clockwise and anticlockwise direction, respectively
(b) Rotation of the electron in anticlockwise and clockwise direction, respectively
(c) Magnetic moment of the electron pointing up and down, respectively
(d) Two quantum mechanical spin states

284. The wavelength associated with a golf ball weighing 200 g and moving at a speed 5 m/h is of the order of:

(a) $10^{-10}m$
(b) $10^{-20}m$
(c) $10^{-30}m$
(d) $10^{-40}m$

285. The no. of 2p electrons having spin quantum number s = -1/2 are:

(a) 6
(b) 0
(c) 2
(d) 3

286. Rutherford’s experiment, which established the nuclear model of the atom, used a beam of:

(a) $\alpha$–particles, which impinged on a metal foil and got absorbed
(b) X-rays, which impinged on a metal foil and ejected electrons
(c) Helium atom, which impinged on a meta foil and got scattered
(d) Helium nuclei, which impinged on a metal foil and got scattered

287. If the nitrogen atom had electronic configuration $1s^7$, it would have energy lower than that of the normal ground state configuration $1s^1, 2s^2, 2p^3$, because the electrons would be closer to the nucleus. Yet $1s^7$ is not observed because it violates,

(a) Heisenberg uncertainty principle
(b) Hund’s rule
(c) Pauli’s exclusion principle
(d) Bohr postulates of stationary orbits

288. How many moles of electrons weigh one kg. (mass of electron = $9.108 \times 10^{-31} kg$, (Avogadro number = $6.023 \times 10^{23}$)

(a) $6.023 \times 10^{23}$
(b) $\dfrac{1}{9.108} \times 10^{31}$
(c) $\dfrac{6.023}{9.108} \times 10^{54}$
(d) $\dfrac{1}{9.108 \times 6.023} 10^{8}$

289. Which has maximum number of atoms?

(a) 24 g of C
(b) 56 g of Fe(56)
(c) 27 g of Al
(d) 108 g of Ag (108)

290. Which of the following ions has the maximum magnetic moment?

(a) $Mn^{2+}$
(b) $Fe^{2+}$
(c) $Ti^{2+}$
(d) $Cr^{2+}$

291. In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inter-orbit jumps of the electron for Bohr orbits in an atom of hydrogen?

(a) $3 \to 2$
(b) $5 \to 2$
(c) $4 \to 1$
(d) $2 \to 5$

292. The de Broglie wavelength of a tennis ball of mass 6o g moving with a velocity of 10 meter per second is approximately:

(a) $10^{-33}m$
(b) $10^{-31}m$
(c) $10^{-16}m$
(d) $10^{-25}m$

293. The orbital angular momentum for an electron revolving in an orbit is given by $\sqrt{l(l + 1)} h/ 2 \pi$. This momentum for an s-electron will be given by:

(a) $+1 / 2h /2 \pi$
(b) Zero
(c) $h /2 \pi$
(d) $\sqrt{2}h / 2 \pi$

294. Which one of the following grouping represents a collection of isoelectronic species ? (At numbers Cs-55, Br-35)

(a) $Na^+, C^{2+}, mg^{2+}$
(b) $n^{3-}, F^-, Na^+$
(c) $Be, Al^{3+} Cl^-$
(d) $Ca^{2+}, Cs^+, Br$

295. The number of d-electrons retained in $Fe^{2+}$ (At. Number of Fe = 26) ions is:

(a) 3
(b) 4
(c) 5
(d) 6

296. Which of the following sets of quantum numbers is correct for an electron in 4f orbital?

(a) n = 4, l = 3, m = +4, s = +1/2
(b) n = 4, l = 4, m = -4, s = -1/2
(c) n = 4, l = 3, m = +1, s = +1/2
(d) n = 3, l = 2, m = -2, s = +1/2

297. Consider the ground state of Cr atom (Z = 24). The number of electrons with the azimuthal quantum numbers, l = 1and 2 are, respectively:

(a) 12 and 4
(b) 12 and 5
(c) 16 and 4
(d) 16 and 5

298. The wavelength of the radiation emitted, when in a hydrogen atom electron falls from infinity to stationary state 1, would be (Rydberg constant = $1.097 \times 10^7 m^{-1}$ )

(a) 91 nm
(b) 192 nm
(c) 406 nm
(d) $9.1 \times 10^{-8} nm$

299. The elements with atomic number 9, 17, 35, 53 have a general configuration:

(a) $ns^2 np^3$
(b) $ns^2 np^4$
(c) $ns^2 np^5$
(d) $ns^2 np^1$

300. Which one of the following sets of ions represents the collection of isoelectric species?

(a) $K^+, Ca^{2+}, Se^{3+}, Cl^-$
(b) $Na^+, Ca^{2+}, Sc^{3+}, F^-$
(c) $K^+, Cl^-, Mg^{2+}, Sc^{3+}$
(d) $Na^+, Mg^{2+}, Al^{3+}, Cl^-$

301. Which of the following transition have minimum wave length?

(a) $n_4 \to n_1$
(b) $n_4 \to n_2$
(c) $n_2 \to n_1$
(d) $n_3 \to n_1$

302. Which of the following sequence is correct as per Aufbau principle?

(a) 3s < 3d < 4s < 4p
(b) 1s < 2p < 4s < 3d
(c) 2s < 5s < 4p < 5d
(d) 2s < 2p < 3d < 3p

303. The total number of orbitals possible for principal quantum number n is:

(a) N
(b) $n^2$
(c) 2n
(d) $2n^2$

304. Electronic configuration of deuterium atom is:

(a) $1s^1$
(b) $2s^2$
(c) $2s^1$
(d) $1s^2$

305. The correct set of the four quantum numbers of a 4d electron is:

(a) 4, 2, 1, -1/2
(b) 4, 2, 1, 0
(c) 4, 3, 2, +1/2
(d) 4, 3, -2, +1/2

306. The valence shell electronic configuration of $Cr^{2+}$ opms is:

(a) $4s ^0 3d^4$
(b) $4s ^2 3d^2$
(c) $4s ^2 3d^0$
(d) $3p ^6 4s^2$

307. The energy of the electron in first Bohr’s orbit is -13.6 eV. The energy of the electron in its first excited state is:

(a) -3.4 eV
(b) -27.8 eV
(c) 6.8 eV
(d) $dsp^2$

308. The H-spectrum show:

(a) Heisenberg’s uncertainty principle
(b) Diffraction
(c) Polarization
(d) Presence of quantized energy level

309. Which of the following statements does not form a part of Bohr’s model of hydrogen atom?

(a) Energy of the electrons in the orbit is quantized
(b) The electrons in the orbit nearest the nucleus has the lowest energy
(c) Electrons revolve in different orbits around the nucleus
(d) The position and velocity of the electrons in the orbit cannot be determined simultaneously

310. Electrons will Ist enter into the set of, quantum numbers n = 4, l = 0 or n = 3,l = 2

(a) N = 5, l = 0
(b) Both possible
(c) N = 3, l = 2
(d) Data insufficient

311. Effective magnetic moment of $Sc^{3+}$ ions is:

(a) 1.23
(b) 0
(c) 2.83
(d) 3.87

312. In a multi-electron atom, which of the following orbits described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields?

(i) n = 1, l = 0, m= 0
(ii) n = 2, l = 0, m= 0
(iii) n = 2, l = 1, m= 1
(iv) n = 3, l = 2, m= 1
(v) n = 3, l = 2, m= 0
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (iv) and (v)

313. Which of the following statements in relation to the hydrogen atom is correct?

(a) 3s orbital is lower in energy than 3p orbital
(b) 2p orbital is lower in energy than 3d orbital
(c) Es and 3p orbitals are of lower energy than 3d orbital
(d) 3s, 3p and 3d orbitals all have the same energy

314. Radial nodes present in 3s and 2p orbitals are respectively:

(a) 0, 2
(b) 2, 0
(c) 2, 1
(d) 1, 2

315. Which of the following have maximum number of unpaired electrons:

(a) $Fe^{3+}$
(b) $Fe^{2+}$
(c) $Co^{2+}$
(d) $Co^{3+}$

316. If magnetic quantum number of a given atom represented by-3, then what will be its principal quantum number?

(a) 2
(b) 3
(c) 4
(d) 5

317. According to Bohr’s theory, the angular momentum of an electron in 5 th is:

(a) $10 h / \pi$
(b) $2.5 h / \pi$
(c) $25 h / \pi$
(d) $1 h / \pi$

318. The orientation of an orbital is governed by:

(a) Azimuthal quantum number
(b) Spin quantum number
(c) Magnetic quantum number
(d) Principal quantum number