Q31 / 150 · MHT CET 2026 (11 April Shift 1) · Chemistry
Why zinc does not exhibit variable oxidation states?
- ACompletely filled $4s$ subshell
- Correct answerBCompletely filled $3d$ subshell
- CIncomplete $3d$ subshell
- DIncomplete $4s$ subshell
Solution
The atomic number of zinc is $30$.
The electronic configuration of zinc is $[Ar] 3d^{10} 4s^{2}$.
Zinc loses two electrons from the $4s$ subshell to form $Zn^{2+}$ ion, which has a stable $[Ar] 3d^{10}$ configuration.
Since the $3d$ subshell is completely filled and highly stable, it does not lose any further electrons.
Therefore, zinc does not exhibit variable oxidation states due to its completely filled $3d$ subshell.
Answer: Completely filled $3d$ subshell
The electronic configuration of zinc is $[Ar] 3d^{10} 4s^{2}$.
Zinc loses two electrons from the $4s$ subshell to form $Zn^{2+}$ ion, which has a stable $[Ar] 3d^{10}$ configuration.
Since the $3d$ subshell is completely filled and highly stable, it does not lose any further electrons.
Therefore, zinc does not exhibit variable oxidation states due to its completely filled $3d$ subshell.
Answer: Completely filled $3d$ subshell
Hence, the correct answer is option: 'B'.