Question

Describe the hybridisation in case of PCl5. Why are the axial bonds longer as compared to equatorial bonds?

Answer 1

The structure of PCl5 is trigonal bipyramidal in which three chlorine atioms are at the corners of triangle while two chlorine atoms are axial. Bond length of axial bond is greater than the length of equatorial bond to minimixe the bond pair – bond pair repulsion between axial and equatorial bonds.

Answer 2

Hybridisation is sp3d.
in pcl5 the axial bonds suffer repulsion from the equatorial bonds so they become long