Q.1
The set of quantum numbers not applicable to an electron
  • a) 1, 1, 1, 1/2
  • b) 1, 0, 0, 1/2
  • c) 1, 0, 0 , -1/2
  • d) 2, 0, 0, 1/2
Q.2
The frequency of a wave is 6 × 1015 s–Its wave number would be
  • a) 105 cm–1
  • b) 2 × 107 m–1
  • c) 2 × 107 cm–1
  • d) 2 × 105 cm–1
Q.3
Atomic number and mass number of an element M are 25 and 52 respectively. The number of electrons, protons and neutrons in M2+ ion are respectively
  • a) 25, 25 and 27
  • b) 25, 27 and 25
  • c) 27, 25 and 27
  • d) 23, 25 and 27
Q.4
The maximum number of electrons in an atom which can have n = 4 is
  • a) 4
  • b) 8
  • c) 16
  • d) 32
Q.5
Maximum number of electrons in a subshell with l = 3 and n = 4 is
  • a) 10
  • b) 12
  • c) 14
  • d) 16
Q.6
Assertion : Zn(II) salts are diamagnetic. Reason : Zn2+ ion has one unpaired electron.
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.7
Which of the following has maximum number of unpaired electrons?
  • a) Mg2+
  • b) Ti3+
  • c) Fe2+
  • d) Mn2+
Q.8
A certain metal when irradiated with light (ν = 3.2 × 1016 Hz) emits photo electrons with twice kinetic energy as did photo electrons when the same metal is irradiated by light (ν = 2.0 × 1016 Hz). Calculate ν0 ofelectron?
  • a) 1.2 × 1014 Hz
  • b) 8 × 1015 Hz
  • c) 1.2 × 1016 Hz
  • d) 4 × 1012 Hz
Q.9
Uncertainty in the momentum of an electron is 1.0×10-5 kg m-the uncertainty in its position will be ( h=6.62 ×10-34 kg m2 s-1) ... [ AFMC 1998]
  • a) 1.05 ×10-28 m
  • b) 1.05 ×10-26 m
  • c) 5.27 ×10-30 m
  • d)5.25 ×10-28 m
Q.10
The principal and azimuthal quantum number of electrons in 4f orbitals are
  • a) 4, 2
  • b) 4, 4
  • c) 4, 3
  • d) 3, 4
Q.11
ratio of kinetic energy and potential energy of an electron in a Bohr orbit like hydrogen - like species is
  • a) 1/2
  • b) -1/2
  • c)1
  • d)-1
Q.12
If the energy difference between the ground state and excited state of an atom is 4.4 × 10–19 J. The wavelength of photon required to produce this transition is
  • a) 4.5 × 10–7 m
  • b) 4.5 × 10–7 nm
  • c) 4.5 × 10–7 Å
  • d) 4.5 × 10–7 cm
Q.13
Two particles A and B are in motion. If the wavelength associated with particle A is 5 × 10–8 m ; calculate the wavelength associated with particle B if its momentum is half of A.
  • a) 5 × 10–8 m
  • b) 10–5 cm
  • c) 10–7 cm
  • d) 5 × 10–8 cm
Q.14
Assertion : Angular momentum of an electron in an atom is quantized. Reason : In an atom only those orbits are permitted in which angular momentum of the electron is a natural number multiple of h/2π
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.15
hat is the maximum number of orbitals that can be identified with the following quantum numbers? n = 3, l = l, m l= 0 [AIPMT-2014]
  • a) 1
  • b) 2
  • c) 3
  • d) 4
Q.16
If r1is the radius of the first orbit of hydrogen atom, then the radii of second, third and fourth orbits in term of r1 are
  • a) r12, r13, r14
  • b) 4r1, 9r1, 16r1
  • c) 8r1, 27r1, 64r1
  • d) 2r1, 6r1, 8r1
Q.17
The wavelength of radiation emitted, when in He+ electron falls from infinity to stationary state would be (R = 1.097 × 107 m–1)
  • a) 2.2 × 10–8 m
  • b) 2.2 × 10–9 m
  • c) 120 m
  • d) 22 × 107 m
Q.18
The time taken by the electron in one complete revolution in the nth Bohr’s orbit of the hydrogen atom is
  • a) Inversely proportional to n2
  • b) Directly proportional to n3
  • c) Directly proportional to h/2π
  • d) nversely proportional to n/h
Q.19
The bond order for a species with the configurationσ1s2, σ*1s2, σ2s2, σ*2s2, σ2px1 will be ... [ Haryana CEET 1991]
  • a) 1
  • b) ½
  • c) zero
  • d) 1
Q.20
A p-orbital can accommodate upto
  • a) Four electrons
  • b) Six electrons
  • c) Two electrons
  • d) Eight electrons
Q.21
The four quantum numbers of valence electron of potassium are
  • a) 4, 0, 1, 1/2
  • b) 4, 1, 0, 1/2
  • c) 4, 0, 0, 1/2
  • d) 4, 1, 1, 1/2
Q.22
Quantum numbers for some electrons are given below A : n = 4, l = 1 B : n = 4, l = 0 C : n = 3, l = 2 D : n = 3, l = 1 The correct increasing order of energy of electrons
  • a) A < B < C < D
  • b) D < C < B < A
  • c) D < B < C < A
  • d) C < B < A < D
Q.23
Which of the following electronic level would allow the hydrogen to absorb a photon but not emit a photon?
  • a) 3s
  • b) 2p
  • c) 2s
  • d) 1s
Q.24
The energy absorbed by each molecule (A2) of a substance is 4.4 × 10–19J and bond energy per molecule is 4.0 × 10–19 J. The kinetic energy of the molecule per atom will be [AIPMT (Prelims)-2009]
  • a) 2.2 × 10–19 J
  • b) 2.0 × 10–19 J
  • c) 4.0 × 10–20J
  • d) 2.0 × 10–20J
Q.25
The uncertainty in momentum of an electron is 1 × 10–5 kg-m/s. The uncertainty in its position will be (h = 6.62 × 10–34 kg-m2/s)
  • a) 5.27 × 10–30 m
  • b) 1.05 × 10–26 m
  • c) 1.05 × 10–28 m
  • d) 5.25 × 10–28 m
Q.26
For which of the following options m = 0 for all orbitals?
  • a) 2s, 2px, 3dxy
  • b) 3s ,2pz ,3dz2
  • c) 3s ,2pz ,3dx2 -y2
  • d) 3s, 3px, 3dxy
Q.27
The number of lobes in most of the d-orbitals are
  • a) 6
  • b) 8
  • c) 10
  • d) 4
Q.28
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 × 10–18 J atom–1 and h = 6.625 × 10–34 Js)
  • a) 1.54 × 1015 s–1
  • b) 1.03 × 1015 s–1
  • c) 3.08 × 1015 s–1
  • d) 2.00 × 1015 s–1
Q.29
The total number of atomic orbitals in fourth energy level of an atom is [AIPMT -2011]
  • a) 4
  • b) 8
  • c) 16
  • d) 32
Q.30
Calculate the energy in joule corresponding to light of wavelength 45 nm: (Planck's constant h = 6.63 × 10–34 Js; speed of light c = 3 × 108 ms–1) [AIPMT-2014]
  • a) 6.67 × 1015
  • b) 6.67 × 1011
  • c) 4.42 × 10–15
  • d) 4.42 × 10–18
Q.31
Number of neutron in heavy hydrogen atom is [ MP PMT]
  • a)0
  • b) 1
  • c)2
  • d)3
Q.32
Which of the following statement is incorrect [ BHU 1985]
  • a) The charge on an electron electron and on protons are equal and opposite
  • b) Neutron has no charge
  • c)Electrons and protons have the same weight
  • d)The mass of a proton and neutron are nearly identical
Q.33
The maximum number of electrons in f -subshell is .... [ IIT Ranchi 1988]
  • a) 2
  • b) 8
  • c)14
  • d)32
Q.34
A photon in X region is more energetic than in the visible region; X is [ BHU 1981]
  • a) IR
  • b) UV
  • c) Microwave
  • d) Radiowave
Q.35
Which of the following are possible values of n , l and m for an atom having maximum value of m=+2? [ Pb. PMT 1985]
  • a)n=4, l=3, m=+2
  • b) n=3, l=2, m=-2
  • c)n=3, l=3, m=+2
  • d)n=4, l=3, m=-2
Q.36
The increasing value of e/m ( charge /mass) is .... [ IIT 1984]
  • a) e, p, n, α
  • b) n. p, e, α
  • c)
  • d)n, α, p, e
Q.37
The radius of atom nucleus is of the order of...... [ IIT 1985]
  • a) 10-12 m
  • b) 10-8 m
  • c) 10-15 m
  • d) 10-10 m
Q.38
In the given atom no two electrons can have the same value for all the four quantum numbers. This is called [ CPMT 92]
  • a) Hund's rule
  • b) Aufbau principle
  • c) Uncertainty principle
  • d) Pauli's exclusion principle
Q.39
Cathode rays are [ JIPMER 1987]
  • a)Electromagnetic waves
  • b) Radiation
  • ac)stream of α particles
  • d)stream of electrons
Q.40
Which statement is correct about proton [ MP PMT 1985]
  • a) Proton is nucleus of Deuterium
  • b) proton is α particle
  • c)Proton is ionised hydrogen atom
  • d)proton is ionised hydrogen
Q.41
When the azimuthal quantum number is l=1, the shape of the orbital will be ..[ EAMCET 1982]
  • a)Spherical
  • b) dumbell
  • c)double dumbell
  • d)more complicated
Q.42
There is no difference between 2p and a 3p orbital regarding [ BHU 1981]
  • a) shape
  • b) size
  • c) energy
  • d) value of n
Q.43
Bohr's model can explain ..... [ IIT 1985]
  • a)Spectrum of Hydrogen atom only
  • b) Spectrum of atom or ion containing one electron only
  • c)the spectrum of hydrogen molecule
  • d)The solar spectrum
Q.44
The electron level which allows the hydrogen to absorb photon but not to emit is ... [ IIT1984]
  • a) 1s
  • b) 2s
  • c)2p
  • d)3d
Q.45
Neutral atom ( atomic number > 1) consists of [ CPMT 1982]
  • a) Only protons
  • b) Neutrons + Protons
  • c)Neutrons + electrons
  • d)Neutrons + electrons + protons
Q.46
The quantum number which is designed by letters s, p, d and f instead of number is [ BHU 1980]
  • a) n
  • b) l
  • c) ml
  • d) ms
Q.47
The number of unpaired electrons in carbon atom is .. [ MLNR 1987]
  • a)1
  • b) 2
  • c)3
  • d)4
Q.48
Rutherford's alpha particle scattering experiment eventually led to the conclusion that ... [ IIT 1986]
  • a) mass and energy are related
  • b) electron occupy space around the nucleus
  • c)Neutron are buried deep in the nucleus
  • d)the point of impact with matter can be precisely determined
Q.49
The maximum number of electrons in a subshell for which l=3 i9s .... [ EAMCET 1982]
  • a) 14
  • b) 10
  • c)8
  • d)4
Q.50
" The exact path of electron in 2p-orbital cant be determined" this statement is based on [DPMT 1981]
  • a) Hund's rule
  • b) Bohr's rule
  • c) Uncertainty principle
  • d) Aufbau principle
0 h : 0 m : 1 s