In which of the following octahedral complexes of Co (at. no. 27), will the magnitude of `Delta_o` be the highest?

Options

A. (a) `[Co(CN)_6]^(3-)`
B. (b) `[Co(C_2O_4)_3]^(3-)`
C. (c) `[Co(H_2O)_6]^(3+)`
D. (d) `[Co(NH_3)_6]^(3+)`

Answer

A

Explanation

`CN^(ɵ)` is stronger ligand hence `Delta_0` is highest.