NEET2024Chemistryd and f Block ElementsActual
The E ^ value for the Mn ³⁺ / Mn ²⁺ couple is more positive than that of Cr ³⁺ / Cr ²⁺ or Fe ³⁺ / Fe ²⁺ due to change of
Options
- Ad ^5 to d ^2 configuration
- Bd ^4 to d ^5 configuration
- Cd^3 to d^5 configuration
- Dd^5 to d^4 configuration
Correct answer
B. d ^4 to d ^5 configuration
Step-by-step solution
E _ Mn ³⁺ / Mn ²⁺ ^ E _ Cr ³⁺ / Cr ²⁺ ^ or E _ Fe ³⁺ / Fe ²⁺ ^ Electronic configuration of Mn ³⁺=[ Ar ] 3 d^4 Electronic configuration of Mn ²⁺=[ Ar ] 3 d^5 Electronic configuration of Cr ³⁺=[ Ar ] 3 d^3 Electronic configuration of Cr ²⁺=[ Ar ] 3 d^4 As Mn ³⁺ from d^4 configuration goes to more stable d^5 configuration (Half filled), due to more exchange energy in d^5 configuration.