Using PCl5 as an example. In PCl3 each 3p orbital is involved in bonding. In PCl5 I'm guessing the 3s electrons which are usually P's lone pair of electrons are snatched by the electronegative Cl atoms. I read that P holds the extra electrons from the 2 extra bonds in its 3d orbital. Does that mean 1 bonding electron resides in the s orbital while the other one resides in the d orbital?
