Using the VSEPR theory, what would you predict the shape of the PCI3 molecule to be?

1 Answer
May 23, 2017

Answer:

#"Trigonal pyramidal..............."#

Explanation:

There are 4 regions of electron density around the central phosphorus atom: #3xxP-Cl# bonds, and one phosphorus-centred lone pair. These adopt a tetrahedral geometry as the shape which minimizes electron-pair interactions. But because we describe molecular geometry on the basis of bonding pairs of electrons, symmetry descends to trigonal pyramidal.

Because #ddotP# has a lone pair, which is close to the phosphorus atom, #/_Cl-P-Cl# should be somewhat compressed from #109.5^@#.

en.wikipedia.org/wiki/Phosphorus_trichloride