Q.1
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.2
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.3
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.4
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.5
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.6
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.7
A p-orbital can accommodate upto
  • a) Four electrons
  • b) Six electrons
  • c) Two electrons
  • d) Eight electrons
Q.8
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.9
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.10
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.11
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.12
The number of lobes in most of the d-orbitals are
  • a) 6
  • b) 8
  • c) 10
  • d) 4
Q.13
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.14
Number of neutron in heavy hydrogen atom is [ MP PMT]
  • a)0
  • b) 1
  • c)2
  • d)3
Q.15
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.16
The maximum number of electrons in f -subshell is .... [ IIT Ranchi 1988]
  • a) 2
  • b) 8
  • c)14
  • d)32
Q.17
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.18
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.19
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.20
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.21
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.22
Cathode rays are [ JIPMER 1987]
  • a)Electromagnetic waves
  • b) Radiation
  • ac)stream of α particles
  • d)stream of electrons
Q.23
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.24
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.25
There is no difference between 2p and a 3p orbital regarding [ BHU 1981]
  • a) shape
  • b) size
  • c) energy
  • d) value of n
Q.26
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.27
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.28
Neutral atom ( atomic number > 1) consists of [ CPMT 1982]
  • a) Only protons
  • b) Neutrons + Protons
  • c)Neutrons + electrons
  • d)Neutrons + electrons + protons
Q.29
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.30
The number of unpaired electrons in carbon atom is .. [ MLNR 1987]
  • a)1
  • b) 2
  • c)3
  • d)4
Q.31
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.32
The maximum number of electrons in a subshell for which l=3 i9s .... [ EAMCET 1982]
  • a) 14
  • b) 10
  • c)8
  • d)4
Q.33
" 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
Q.34
MAximum number of electrons present in 'N' shell .... [ EAMCET 1984]
  • a)18
  • b) 32
  • c)2
  • d)8
Q.35
When alpha particles are sent through a thin metal foil, most of them go straight through the foil because ... [ IIT 1994]
  • a) alpha particles are mush heavier than electron
  • b) alpha particles are positive charged
  • c)alpha particles move with high velocity
  • d)most part of atom is empty
Q.36
Which of the following is not correct for electronic distribution in the ground state [ AIIMS 1982]
  • a)
    ch-1_qn-303choice_img_no1.png
  • b)
    ch-1_qn-303choice_img_no2.png
  • c)
    ch-1_qn-303choice_img_no3.png
  • d)
    ch-1_qn-303choice_img_no4.png
Q.37
the ratio of the difference in energy between the first and the second Bohr orbit to that between the second and the third Bohr orbit is [ NCERT1980]
  • a) 1:2
  • b) 1:3
  • c) 4:9
  • d) 27:5
Q.38
The volume of nucleus is about [ eamcet 1986]
  • a)10-15 times that of atom
  • b) 10-10 times that of atom
  • c)10-15 times that of atom
  • d)10-20 times that of atom
Q.39
Which one of the following sets of quantum numbers represents an impossible arrangement? [ IIT 1986]
  • a) n=3, l=2, ml=-2, ms=1/2
  • b) n=4, l=0, ml=0, ms=1/2
  • c)n=3, l=2, ml=-2, ms=1/2
  • d)n=5, l=3, ml=0, ms=1/2
Q.40
Remaining part of atom except outer orbit is called [ CPMT 1982]
  • a)Kernel
  • b) Core
  • c)Empty space
  • d)None
Q.41
How many unpaired electrons are there in NI2+ [ IIT 1981]
  • a) 0
  • b) 2
  • c) 4
  • d) 8
Q.42
Which quantum number is sufficient to describe the electron in hydrogen atom .... [ CPMT 1984]
  • a)l
  • b) n
  • c)m
  • d)s
Q.43
The symbol of the element whose atoms have the outer most electronic configuration 2s2, 2p3 is ... [ EAMCET 1983]
  • a) N
  • b) Li
  • c)P
  • d)Na
Q.44
The maximum number of electrons in p-orbital with n=0 and m=0 is [ EAMCET 1981]
  • a) 2
  • b) 6
  • c)10
  • d)14
Q.45
The ratio of the radii of the first three Bohr orbits is [ NCERT 1980]
  • a) 1:0.5:0.33
  • b) 1:2:3
  • c) 1:4:9
  • d) 1:8:27
Q.46
The atomic weight of an element is 23 and atomic number isThe number of protons, electrons and neutrons respectively present in the atom of the element are [ AFMC 89]
  • a)11, 11, 12
  • b) 12, 12, 11
  • c)11,12, 11
  • d)12,11,12
Q.47
The number of unpaired electrons in Cr+3 ( atomic number 24) is [ MLNR 1986]
  • a) 6
  • b) 4
  • c)3
  • d)1
Q.48
Cathode rays are deflected by ..... [ CPMT 1982]
  • a) an electric filed only
  • b) a magnetic field only
  • c)by both
  • d)by none
Q.49
Rutherford's experiment on scattering of particles showed for the first time that the atom has [ IIT1981]
  • a) Electrons
  • b) Protons
  • c) Nucleus
  • d) Neutrons
Q.50
As we move away from nucleus, the energy of orbit .... [ DPMT 1984]
  • a)Decreases
  • b) Increases
  • c)remains uncharged
  • d)none of these
0 h : 0 m : 1 s