Which will be the most stble among ` Cu^(+) , Fe^(+) Fe^(2+)` and `Fe^(3+)`.

Options

A. `Fe^(2+)`
B. `Fe^(+)`
C. ` Cu^(+)`
D. `Fe^(3+)`

Answer

D

Explanation

`Fe^(3+)` has `3d^(5)` configuration , i. e,. A half fillled one and thuss mor stable ` cu^(+)` no doubt has ` 3d^(10)` configuration but less stable because nuclear cahrge ( 29 protons ) in `Cu` is not sufficient enough to hold a core fo `18` electrons .