Chapter-2: Structure of Atom

1. The credit of discovering neutron goes to

  • Rutherford
  • Thomson
  • Goldstein
  • Chadwick
Answer
Chadwick

2. For principal quantum number n = 4, the total number of orbitals having l = 3 is

  • 3
  • 7
  • 5
  • 9
Answer
7

3. The maximum number of electrons that can be accommodated in fifth energy level is

  • 10
  • 25
  • 50
  • 32
Answer
50

4. The electronic transitions from n = 2 to n = 1 will produce shortest wavelength in (where n = principal quantum state)

  • Li2+
  • He+
  • H
  • H+
Answer
Li2+

5. The magnetic quantum number specifies

  • Size of orbitals
  • Shape of orbitals
  • Orientation of orbitals
  • Nuclear Stability
Answer
Orientation of orbitals

6. Maximum number of electrons in a subshell with l = 3 and n = 4 is

  • 10
  • 12
  • 14
  • 16
Answer
14

7. The charge to mass ratio of α – particles is approximately …… the charge to mass ratio of protons

  • Twice
  • Half
  • Four times
  • Six times
Answer
Half

8. In chromium atom, in ground state, the number of occupied orbitals is

  • 14
  • 15
  • 7
  • 12
Answer
15

9. Which hydrogen-like species will have same radius as that of Bohr orbit of hydrogen atom?

  • n = 2, Li2+
  • n = 2, Be3+
  • n = 2, He+
  • n = 3, Li2+
Answer
n = 2, Be3+

10. Which of the following pair of ions have same paramagnetic moment?

  • Cu+2, Ti+3
  • Mn+2, Cu+2
  • Ti+4, Cu+2
  • Ti+3, Ni+2
Answer
Cu+2, Ti+3

11. Which of the following sets of quantum numbers represents the highest energy of an atom?

  • n = 3, l = 0, m = 0, s = +1/2
  • n = 3, l = 1, m = 1, s = +1/2
  • n = 3, l = 2, m = 1, s = +1/2
  • n = 4, l = 0, m = 0, s = +1/2
Answer
n = 3, l = 2, m = 1, s = +1/2

12. In a hydrogen atom, if energy of an electron in ground state is 13.6 eV, then that in the 2nd excited state is

  • 1.51 eV
  • 3.4 eV
  • 6.04 eV
  • 13.6 eV
Answer
1.51 eV

13. A sub-shell with n = 6 , l = 2 can accommodate a maximum of

  • 12 electrons
  • 36 electrons
  • 10 electrons
  • 72 electrons
Answer
10 electrons

14. The frequency of a wave of light is 12 × 1014s-1. The wave number associated with this light

  • 5 × 10-7m
  • 4 × 10-8cm-1
  • 2 × 10-7m-1
  • 4 × 104cm-1
Answer
4 × 104cm-1

15. According to Aufbaus principle, which of the three 4d, 5p and 5s will be filled with electrons first

  • 4d
  • 5p
  • 5s
  • 4d and 5s will be filled simultaneously
Answer
5s