Lewis Dot of Phosphorous Pentachloride
P does not follow the octet rule. It will hold more than 8 electrons.
Phosphorous having valence electrons in the 3rd energy level, will also have access to the 3d sublevel, thus allowing for more than 8 electrons.
It will hybridize to form 5 equal dsp3 orbitals and will have a trigonal bipyramidal shape.
Elements in the first 2 periods of the Periodic Table do not have access to the d sublevel and must adhere to the octet (or duet H and He) rule.