Problem
PCl5 is a white solid, which volatilises at 160oC and melts at 148oC
under pressure. Molten PCl5 conducts an electric current readily. At
180oC PCl5 vapour has a density of 9.3 g/L corrected to the standard
conditions. At 250oC a sample of PCl5 exerts a pressure, which is twice
the expected value. Discuss these observations and comment on the
species present in the melt and at 180o and 250o in the vapour.
