A coordination complex exhibits a spin-only magnetic moment of 3.87 BM. Which of the following is the correct formula of the complex?

Step-by-step solution

The spin-only magnetic moment is given by = n(n+2) BM, where n is the number of unpaired electrons. Given = 3.87 BM, we have n(n+2) = 3.87 , which gives n = 3 . Let us check the number of unpaired electrons in each complex: [Cr(H₂O)₆]³⁺ : Cr³⁺ has a 3d^3 configuration. In an octahedral field, it forms a t_ 2g ^3 e_g^0 configuration with 3 unpaired electrons. [V(H₂O)₆]³⁺ : V³⁺ has a 3d^2 configuration, giving 2 unpaired electrons. [Mn(CN)₆]³⁻ : Mn³⁺ is 3d^4 . Since CN^- is a strong field ligand, pairing occurs to gi