In which of the following complex ion the value of magnetic moment (spin only) is `sqrt(3)`B.M. and oute rd-orbitals is used in hybridization:

Options

A. `[Fe(NH_(3))_(6)]^(3+)`
B. `[Mn(CN)_(6)]^(4-)`
C. `[CuCl_(5)]^(2-)`
D. `[Co(NH_(3))_(6)]^(2+)`

Answer

A

Explanation

`[CuCl_(5)]^(2-),sp^(3)` d-hybridisation (outer orbital complex) (magnetic moment`=sqrt(3)` B.M.)
`[Fe(NH_(3))_(6)]^(3+),[Mn(CN)_(6)]^(4-) and [Co(NH_(3))_(6)]^(2+)` are inner orbital complexes and are also paramagnetic in nature having magnetic moment of `sqrt(3)B.M.`