Question

What can be inferred from the magnetic moment values of the following complex species ?
Example
K₄[Mn(Cn)₆]
[Fe(H₂O)₆]²⁺
K₂[MnCl₄]

Magnetic Moment (BM)
2.2
5.3
5.9

Answer 1

(i) √(n(n+2)) = 2.2.

The given value is almost n = 1. In the complex, Mn is in +2 oxidation state.

It means that the Mn has almost 5 electrons in d-orbital.

CN- causes pairing of the electrons. (ii)√(n(n+2)) = 5.3.

Here the given value is almost n=4.

H2O does not cause pairing of electrons. (iii)√(n(n+2)) = 5.9. Here the given value is almost n=5.

Cl- does not cause pairing of electrons.