This experiment is fraught with danger. Phosphorus itself is a real killer -
Concentrated sulphuric acid is highly corrosive, and the gaseous product of the reaction, phosphine, is deadly. The phosphorus pentoxide produced when the phosphine spontaneously ignites won`t do you any good either. An experiment only for the experienced chemist, to be performed in a fume cupboard.
More about phosphine can be found here - phosphorus