Question

The magnetic moments (spin only) of $\left[Ni\right(Cl{)}_4){]}^{2-}$ and $\left[Ni\right(CN{)}_4){]}^{2-}$ are:

• A. 0 B.M , 0 B.M
• B. 2.82 B.M, 2.82 B.M
• C. 0 B.M, 2.82 B.M
• D. 2.82 B.M, 0 B.M

Answer 1

The correct option is D 2.82 B.M, 0 B.M

In $[NiC{l}_4{]}^{-2}$, $N{i}^{+2}$ has $d^8$ configuration and is a high spin complex. It has $s{p}^3$ hybridization, tetrahedral structure and 2 unpaired electron.
So magnetic moment, $\mu =\sqrt{n(n+2)}=\sqrt{2\times 4}=2.82$ BM.

In $Ni(CN{)}_4^{-2}$, $N{i}^{+2}$ has $d^8$ configuration, low spin complex, $ds{p}^2$ hybridization, square planar structure and zero unpaired electron.
So magnetic moment, $\mu =\sqrt{n(n+2)}=0$ .

Option D is correct.