For the coordinate complexes involving central metal ions, which of the following correlations betwe — Coordination Compounds Chemistry Question

💡 Solution & Explanation

A central metal with a $d^8$ configuration (like $Ni^{2+}$) behaves differently based on ligand strength. Weak field ligands (like $Cl^-$) do not force pairing, leading to $sp^3$ hybridization and tetrahedral geometry (A is true). Strong field ligands (like $CN^-$) force pairing, leaving one $3d$ orbital free for $dsp^2$ hybridization, yielding a square planar geometry (B is true). $[NiCl_4]^{2-}$ is tetrahedral (C is true). $[Ni(CN)_4]^{2-}$ is square planar, not octahedral (D is false).