The magnetic moment (spin only) of NiCl42− is

NiCl42−; oxidation number of Ni, x - 4 = -2∴ x=+2, Ni28Ar3d8,4s2sp3-hybrid orbitals, tetrahedralSince, Cl- is a weak ligand, thus unpaired electrons are not paired. Lone pairs from 4 Cl- are accommodated in four sp3hybrid orbitals.n = unpaired electron = 2, paramagneticMagnetic moment (spin only)=nn+2BM=8=2.828 BM