White to yellow solid with an offensive odor
Molecular Formula	PCl5	Molecular Weight	208.22
Boiling Point	Sublimes	Melting Point	162°C
Vapor Density	7.2	Liquid Density	3.6
Vapor pressure	133 Pa at 55.5°C
Not flammable

Also refer to 2000 Emergency Response Guidebook (ERG2000) Guide 137.

Health Hazards

Phosphorus pentachloride is considered an extremely hazardous substance. It is not flammable but decomposes in fire to release toxic products. It reacts violently with water with the release of hydrogen chloride. It is damaging to all exposed surfaces and tissues and protective clothing and equipment must be worn when handling. Although the oral LD₅₀ for rats is relatively high at 660 mg/kg, it can be severely damaging at lower concentrations. Tolerated atmospheric levels are extremely low.

Risk and Safety Phrases.

INDUSTRIAL/COMMERCIAL USES

Phosphorus pentachloride is not as widely used in industrial chemistry as phosphorus trichloride. It is used as a chlorinating agent and it is preferred to the trichloride in some reactions, and in small quantities it is used as a catalyst. The commonest use of phosphorus trichloride is in the manufacture of chlorophosphazenes, a group of flame retardants. It is also used in lithium-based batteries. Phosphorus pentachloride is manufactured from the trichloride by reaction with chlorine gas in carbon tetrachlorideas a solvent.

COMMENTS

Phosphorus pentachloride can be used in the synthesis of G-type nerve agents including sarin and cyclosarin. It is a versatile chlorinating agent and may be useful in other syntheses.