Assertion : Reduction potential of Mn ( + 3 to + 2) is more positive than that of Fe ( + 3 to + 2). Reason : Ionisation potential of Mn is more than t

Monjur Alahi

Assertion : Reduction potential of Mn ( + 3 to + 2) is more positive than that of Fe ( + 3 to + 2).
Reason : Ionisation potential of Mn is more than that of Fe.
A. If both assertion and reason are correct and reason is correct explanation for assertion.
B. If both assertion and reason are correct but reason is not correct not correct explanation for assertion.
C. If assertion is correct but reason is incorrect.
D. If both assertion and reason are incorrect.


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Salim Ahmed Kawsar

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Correct Answer - C
(c) Correct reason. `Mn^(2+)" "(3d^(5))` has more stable configuration than `Mn^(3+)" "(3d^(4))` while `Fe^(3+)" "(3d^(5))` has more stable configuration than `Fe^(2+)" "(3d^(6))`. Therefore, `E_(Mn^(3+)//Mn^(2+))^(@)` couple is more positive than `Fe^(3+)//Fe^(2+)` couple.

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