Question:
Predict the number of unpaired electrons in the square planar [Pt(CN)4]2− ion.
Solution:
In this complex, Pt is in the +2 state. It forms a square planar structure. This means that it undergoes dsp2 hybridization. Now, the electronic configuration of Pd(+2) is 5d8.
$\mathrm{CN}^{-}$being a strong field ligand causes the pairing of unpaired electrons. Hence, there are no unpaired electrons in $\left[\mathrm{Pt}(\mathrm{CN})_{4}\right]^{2-}$.