Account for the different magnetic behaviour of hexacyanoferrate (III) and hexafluoroferrate(III).

Explanation

`[Fe(CN)_6]^(3+)`
O.S. of Fe = +3`" "`E.C. of `Fe^(3+)` : `3d^5`
After pairing no. of unpaired electrons = 1
Hence complete is weakly paramagnetic.
`[FeF_6]^(3-)`
O.S. of Fe = +3`" "`E.C. of `Fe^(3+)` : `3d^5`
No pairing, hence no. of unpaired electrons = 4
Hence complex is strongly paramagnetic.