What is the number of unpaired electrons of nickel observed in $\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{-2}$
What is the number of unpaired electrons of nickel observed in $\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{-2}$
6
2
4
zero
Solution
$\mathrm{Ni}^{+2}=[\mathrm{Ar}] 3 \mathrm{~d}^8$
As $\mathrm{CN}^{-}$is a strong field ligand therefore passing of $\mathrm{e}^{-} \mathrm{s}^{\text {takes }}$ place $\mathrm{Ni}^{+2}=[\mathrm{Ar}]$
