Which of the following is an inner orbital complex as well as diamagnetic in behaviour
[Atomic numbers Zn = 30, Cr = 24, Co = 27, Ni = 28.]

Options

A. `[Zn(NH_3)_6]^(2+)`
B. `[Cr(NH_3)_6]^(3+)`
C. `[Co(NH_3)_6]^(3+)`
D. `[Ni(NH_3)_6]^(2+)`

Answer

C

Explanation

Due to paired `e^-` it is diamagnetic.