The geometry of [Ni(CO)4] and [NiCl2(PPh3)2] are : — Coordination Compounds Chemistry Question

💡 Solution & Explanation

Step 1: In [Ni(CO)4], Nickel is in the 0 oxidation state (3d^10 4s^2). The strong-field carbonyl ligands force the s-electrons into the d-orbitals, giving a completely filled 3d^10 configuration, resulting in sp^3 hybridization (tetrahedral geometry). Step 2: In [NiCl2(PPh3)2], Nickel is in the +2 oxidation state (3d^8). Although PPh3 is a strong-field ligand, its extreme steric bulk forces a tetrahedral geometry over a square planar one to minimize steric repulsions. Step 3: Thus, both complexes adopt a tetrahedral geometry, which matches option (c).