Electronic Configuration of Elements, Extra Stability of Half-Filled and Completely Filled Orbitals. NEET Questions

Physical Chemistry - Atomic Structure

Electronic Configuration of Elements, Extra Stability of Half-Filled and Completely Filled Orbitals. MCQ Questions


1.
The electronic configuration of an element with atomic number 24 (Cr) is:
A.
[Ar] 3d⁶ 4s⁰
B.
[Ar] 3d⁴ 4s²
C.
[Ar] 3d³ 4s² 4p¹
D.
[Ar] 3d⁵ 4s¹
😑 View Answer Rough Work Error
ANSWER :
D. [Ar] 3d⁵ 4s¹
2.
The correct ground state electronic configuration of Cu (Z=29) is:
A.
[Ar] 3d⁷ 4s² 4p²
B.
[Ar] 3d¹⁰ 4s¹
C.
[Ar] 3d⁹ 4s²
D.
[Ar] 3d⁸ 4s² 4p¹
😑 View Answer Rough Work Error
ANSWER :
B. [Ar] 3d¹⁰ 4s¹
3.
Which of the following statements about the stability of half-filled and fully-filled orbitals is INCORRECT?
A.
Both half-filled and fully-filled subshells have higher energy than partially filled ones
B.
Symmetrical distribution of electrons makes them stable
C.
Exchange energy contributes to extra stability
D.
Smaller coulombic repulsion contributes to stability
😑 View Answer Rough Work Error
ANSWER :
A. Both half-filled and fully-filled subshells have higher energy than partially filled ones
4.
The total number of electrons that can be accommodated in all the orbitals having principal quantum number 3 and azimuthal quantum number 2 is:
A.
14
B.
6
C.
10
D.
2
😑 View Answer Rough Work Error
ANSWER :
C. 10
5.
According to Aufbau principle, which orbital is filled after 4p?
A.
5s
B.
4f
C.
4d
D.
5p
😑 View Answer Rough Work Error
ANSWER :
A. 5s
6.
The electronic configuration of Mn²⁺ ion (Z of Mn = 25) is:
A.
[Ar] 3d⁵ 4s²
B.
[Ar] 3d³ 4s²
C.
[Ar] 3d⁴ 4s¹
D.
[Ar] 3d⁵ 4s⁰
😑 View Answer Rough Work Error
ANSWER :
D. [Ar] 3d⁵ 4s⁰