Correct increasing order of wavelength of absorption in visible region for complex of `CO^(3+)` is :

Options

A. `[Co(H_2O)_6]^(3+),[Co(en)_3]^(3+),[Co(NH_3)_6]^(3+)`
B. `[Co(H_2O)_6]^(3+) ,[Co(NH_3)_6]^(3+),[Co(en)_3]^(3+)`
C. `[Co(NH_3)_6]^(3+),[Co(en)_3]^(3+), [Co(H_2O)_6]^(3+)`
D. `[Co(en)_3]^(3+) , [Co(NH_3)_6]^(3+) , [ Co(H_2O)_6]^(3+)`

Answer

D

Explanation

since en is bidentate ligand will form stable complex will form stable complex will absorb highest energy but lowest wavelength.
`[Co(H_2O)_6]^(3+)` will absorb lowest energy,highest wavelength.