Amongst the following, the most stable complex is -

Options

A. `[Fe(H_(2)O)_(6)]^(3+)`
B. `[Fe(NH_(3))_(6)]^(3+)`
C. `[Fe(C_(2)O_(4))_(3)]^(3-)`
D. `[FeCl_(6)]^(3-)`

Explanation

In each of the given complexes, the central metal atom `(Fe)` is in `+3` oxidation state. Since `C_(2)O_(4)^(2-)` is a didentate ligand, it forms stable chelate ring with `Fe^(3+)` ion and hence `[Fe(C_(2)O_(4))_(3)]^(3-)` is the most stable complex.