$\mathrm{Ni}: 3 d^8 4 s^2 \quad \mathrm{Ni}^{2+}: 3 d^8$
Since, $\mathrm{Cl}$ is a weak field ligand, it doesn't cause pairing of electron.


Number of unpaired electrons, $n=2$

\mu=\sqrt{n(n+2)}=\sqrt{2(2+2)} \mathrm{BM}=\sqrt{8} \mathrm{BM}=2.82 \mathrm{BM}

Coordination compound
Conceptual
III