Q 1. Bohr’s model can explain
(A) The 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 2. The radius of hydrogen atom is 0.53Ḁ̥̥ . The radius of 3Li2+ is of
(A) 1.27 A (B) 0.17 A (C) 0.57 A (D) 0.99 A
Q 3. The spectrum of He is expected to be similar to
(A) H (B) Li+ (C) Na (D) He+
Q 4. The energy of an electron in nth orbit of hydrogen atom is
(A) 13.6/n2eV (B) 13.6/n3eV (C) 13.6/n2eV (D) 13.6/ n eV
Q 5. According to Bohr’s theory , the angular momentum of an electron in 5th orbit is
(A) 2.5h / π (B)1.0 h / π (C) 10 h / π (D) 10 h / π
Q 6. If electron falls n = 3 to n = 2 , then emitted energy is
(A) 10.2eV (B) 12.09eV (C) 1.9eV (D) 0.65eV
Q 7. The energy of a photon is calculated by
(A) E = hv (B) h = Ev (C) h = E/V (D) E = h/v
Q8.Radius of the first Bohr’s orbit of hydrogen atom is
(A)1.06 A (B) 0.22 A (C) 0.28 A (D) 0.53 A
Q 9. The radius of first Bohr’s orbit for hydrogen is 0.53 A. The radius of third Bohr’s orbit would be
(A) 0.79 A (B) 1.59 A (C) 3.18 A (D) 4.77 A
Q 10. The value of the energy for the first excited state of hydrogen atom will be
(A) – 13.6eV (B) -3.40eV (C) – 1.51eV (D) -0.85eV
Q 11. Ratio of radii of second and first Bohr orbit of H atom
(A) 2 (B) 4 (C) 3 (D) 5
Q 12. The radius of the first Bohr orbit of the H atom is r. Then the radius of the orbit of Li2+ will be
(A) r/9 (B) r/3 (C) 3r (D) 9r
Q 13.The shape of an orbital is given by the quantum number
(A) n (B) l (C) m (D) s
Q 14. In a given atom no two electron can have the same values for the four quantum number. This is called
(A) Hund’s rule (B) Aufbau’s principle (C) Uncertainty principle (D) Pauli‘s exclusive principle
Q 15. The electronic configuration of silver atom in ground state is
(A) [Kr]3d10 (B) [Xe]4f145d106s1
(C) [Kr]4d105s1 (D) [Kr]4d95d2s
Q 16. The correct ground state electronic configuration of chromium atom is
(A) [Ar]3d5 4s1 (B) [Ar]3d4 4s2
(C) [Ar]3d6 4s0(D) [Ar]4d5 4s1
Q 17. 2p orbitals have
(A) n = 1,l = 2 (B) n = 1, l = 0
(C) n = 2, l = 1 (D) n = 2, l = 0
Q 18. Principle quantum number of atom represents
(A) Size of the orbit (B) Spin angular momentum
(C) Orbital angular momentum
(D) Space orientation of the orbital
Q 19. The number of electrons in the valence shell of calcium is
(A) 6 (B) 8 (C) 4 (D) 4
Q 20. The electronic configuration of calcium ion (Ca2+) is
(A) 1s2,2s2 2p6 ,3s2 ,3p6 ,4s2 (B) 1s2,2s2 2p6 ,3s2 ,3p6 ,4s1
(C) 1s2,2s2 2p6 ,3s2 ,3p6 ,4d2 (D) 1s2,2s2 2p6 ,3s2 ,3p6 ,4d5
(E) 1s2,2s2 2p6 ,3s2 ,3p6 ,4s0
Q 21.Which of the following is non – permissible
(A) n = 4, l = 3, m = 0 (B) n = 4, l = 2, m = 1 (C) n = 4, l = 4, m = 1 (D) n = 4, l = 0, m = 0
Q 22. The following quantum number are possible for how many orbitals n = 0 or n = 3, 1 = +2
(A) 3 (B) 2 (C) 1 (D) 4
Q 23. The number of orbital in d sub – shell is
(A) 1 (B) 3 (C) 5 (D) 7
Q 24. For p – orbital, the magnetic quantum number has value
(A) 2 (B) 4, – 4 (C) – 1, 0, +1 (D) 0
Q 25. The shape of s – orbital is
(A) Pyramidal (B) Spherical
(C)Tetrahedral (D) Dumb – bell shaped
Q 26. For azimuthal quantum number l = 3, the maximum number of electrons will be or Maximum number of electrons in a subshell with l = 3 and n = 4 is
(A) 2 (B) 6 (C) 0 (D) 14
Q 27.Px orbital can accommodate
(A) 4 electron (B) 6 electron (C) 2 electron with parallel spins (D) 2 electron with opposite spins
Q 28. Number of unpaired electrons in 1s22s22p3 is
(A) 2 (B) 0 (C) 3 (D)1
Q 30. How many unpaired electrons are present in Ni2+ cation (atomic number = 28)
(A) 0 (B) 2 (C) 4 (D) 6
Q 31 The electronic configuration 1s22s22px12py12pz1 is of
(A) Oxygen (B) Nitrogen (C) Hydrogen (D) Fluorine
Q 32. If n = 3 then value of ‘l’ with is incorrect
(A) 0 (B) 1 (C) 2 (D) 3
Q 33. Which orbital is dumb – bell shaped
(A) s – orbital (B) p – orbital (C) d – orbital (D) f – orbital
Q 34.Which of the following sets of quantum number represents the highest energy of an atom
(A) n = 3, l = 2, m = 1, s = +1/2(B) n =3, l = 2, m = 1, s = -1/2 (C) n = 4, l = 0, m = 0, s = +1/2 (D) n = 3, l = 0, m = 0, s = +1/2