F.5Chemistry-microscopic world

In PCl3, the central atom is P. There are 3 bond pairs (3 P-Cl bonds) and 1 lone pair of electrons. According to the VSEPR theory, the 4 electron pairs are spatially arranged as tetrahedral.

In determination of the shape of a molecule, only the central atom and the atoms attached directly to the central atoms are to be considered. Therefore, in consider the shape of PCl3 molecules, only the central P atom and the 3 Cl atoms are considered. Therefore, the shape of PCl3­ is considered as triangular pyramidal.