NEET2011Chemistryd and f Block ElementsActual
Assertion : Reduction potential of Mn (+3 to +2 ) is more positive than Fe (+3 to +2 ) . Reason : Ionisation potential of Mnis more than that of Fe .
Options
- AIf both assertion and reason are true and reason is the correct explanation of assertion.
- BIf both assertion and reason are true but reason is not the correct explanation of assertion.
- CIf assertion is true but reason is false.
- DIf both assertion and reason are false.
Correct answer
C. If assertion is true but reason is false.
Step-by-step solution
Mn ²⁺=[ Ar ] 3 d^5 aligned & Mn ³⁺=[ Ar ] 3 d^4 & Fe ³⁺=[ Ar ] 3 d^5 aligned Fe ²⁺=[ Ar ] 3 d^6 , Thus, Mn ²⁺ has more stable configuration than Mn ³⁺ while Fe ³⁺ has more stable configuration than Fe ²⁺ . Hence, reduction potential for Mn ³⁺ / Mn ²⁺ couple is more positive than Fe ³⁺ / Fe ²⁺ .