Why `Mn^(2+)` compounds are more stable than `Fe^(2+)` compounds towards oxidation to their + 3 state ?

Options

A. `Mn^(2+)` is more stable with high 3rd ionisation energy
B. `Mn^(2+)` is bigger in size
C. `Mn^+` has completely filled d-orbitals
D. `Mn^(2+)` does not exist

Answer

A

Explanation

Electronic configuration of `Mn^(2+)` is `[Ar] 3d^5` . It has stable half filled configuration. Therefore, it has a high 3rd ionisation energy and is stable towards oxidation to their +3 oxidation state.