Consider the following coordination complexes: [ MnCl ₄ ]²⁻ , [ Co(ox) ₃ ]³⁻ , [ V(H ₂ O) ₆ ]²⁺ , and [ PdCl ₄ ]²⁻ The sum of the squares of the spin-only magnetic moments (in BM ^2 ) of these complexes is

Step-by-step solution

1. [ MnCl ₄ ]²⁻ : Mn is in +2 oxidation state ( 3 d ^5 ). Cl ^- is a weak field ligand. It forms a high-spin tetrahedral complex with 5 unpaired electrons. ^2 = n(n+2) = 5(5+2) = 35 . 2. [ Co(ox) ₃ ]³⁻ : Co is in +3 oxidation state ( 3 d ^6 ). Oxalate ( ox ²⁻ ) acts as a strong field ligand for Co ³⁺ , causing electron pairing. It forms a diamagnetic octahedral complex with 0 unpaired electrons. ^2 = 0 . 3. [ V(H ₂ O) ₆ ]²⁺ : V is in +2 oxidation state ( 3 d ^3 ). It has 3 unpaired electrons. ^2 = 3(3+2) = 15 . 4.