Which is a stronger reducing agent `Cr^(2+) or Fe^(2+)` and why ?

Explanation

`Cr^(2+)` is stronger reducing agent than `Fe^(2+)`, because `d^(4)rarr d^(3)` occurs in case of `Cr^(2+)" to Cr^(3+)` but `d^(6)rarr d^(5)` occurs in case of `Fe^(2+)` to `Fe^(3+)`. In aqueous solution, `d^(3)` is more stable as compared to `d^(5)`.