Phosphorus Pentachloride is a water sensitive & colorless chlorinating agent having molecular formula Cl5P and molar mass of 208.22 g/mol with unpleasant odor. It can industrially be prepared by chlorination of PCl3 and shows solubility in benzene & chlorocarbons. With density of 2.1 g/cm3, this compound has melting & boiling points of 160.5 & 166.8 degrees Celsius. Considered as one of the most important phosphorus chlorides, it also shows sensitivity against moisture. Phosphorus Pentachloride is a phosphorus halide having pungent or irritating odor with corrosive nature for metals. It also serves as catalyst in manufacturing of acetylcellulose that works by replacing hydroxyl groups in place of Cl.