Which of the following pairs of coordination compounds has the same value of spin-only magnetic moment?

Step-by-step solution

In [ CoF ₆ ]³⁻ , Co is in +3 oxidation state ( 3 d ⁶ ). F ⁻ is a weak field ligand, so it forms a high spin complex with configuration t _ 2 g ⁴ e _ g ² . Number of unpaired electrons ( n ) = 4. In [ Fe ( H ₂ O )₆ ]²⁺ , Fe is in +2 oxidation state ( 3 d ⁶ ). H ₂ O is a weak field ligand, so it forms a high spin complex with configuration t _ 2 g ⁴ e _ g ² . Number of unpaired electrons ( n ) = 4. Since both have n=4 , their spin-only magnetic moment is 4(4+2) = 24 = 4.90 BM . For other options: [ Mn ( CN )₆ ]³⁻ : M