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^(2+)` has completely filled d-orbitals
D. `Mn^(2+)` does not exist

Answer

A

Explanation

`Mn^(2+)` has stable half-filled electronic configuration thus, it has high third ionisation energy while `Fe^(2+)` on losing one more electron will acquire this stable electronic configuration. Thus, `Fe^(2+)` is more prone to get oxidised to +3 oxidation state.