Consider the following complex ions, P, Q and R.
`P=[FeF_(6)[^(3-),Q=[V(H_(2)O)_(6)]^(2+) and R=[Fe(H_(2)O)_(6)]^(2+)` The correct order of the complex ions, according to their spin-only magnetic moment values (in B.M.) is

Options

A. `R lt Q lt P`
B. `Q lt R lt P`
C. `R lt P lt Q`
D. `Q lt P lt R`

Answer

B

Explanation

The electronic configuration of central ion in complex ions P, Q and R are

Higher the no. of unpaired electron(s), higher will be magnetic moment. Thus the correct order of spin only magnetic moment is QltRltP.