Question

PCl5 molecule is unsymmetric.Why?

Answer 1

there is a theoretical reason (VSEPR) for PCl5 to be non-polar. The electron pairs in the five P-Cl bonds repel each other (while being attracted to the phosphorus nucleus). ... For a contrast, consider PCl3, which has a trigonal pyramid geometry (with a lone pair on the phosphorus atom) according to VSEPR theory.

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