Question

Among the following complex ions, which is diamagnetic in nature is

• A. $[Co{F}_6{]}^{3-}$
• B. $[NiC{l}_4{]}^{2-}$
• C. $\left[Ni\right(CN{)}_4{]}^{2-}$
• D. $[CuC{l}_4{]}^{2-}$

Answer 1

The correct option is C $\left[Ni\right(CN{)}_4{]}^{2-}$

In $\left[Ni\right(CN{)}_4{]}^{2-}$, Ni has $ds{p}^2$ hybridisation where, $C{N}^{-}$ is a strong ligand. Hence, all electrons in 3d are paired.