Phosphorus pentasulfide, is a nonmetallic inorganic compound . It is a yellow to greenish-yellow crystalline mass with an odor similar to hydrogen sulfide. It is a dangerous fire risk and ignites by friction or in contact with water. Boiling point is 995°F (535°C) and ignition temperature is 287°F (141°C). It decomposes upon contact with water or moist air, liberating toxic and flammable hydrogen-sulfide gas. Specific gravity is 2.09, so it is heavier than water. It is toxic by inhalation, with a TLV of 1 mg/m3 of air. The four-digit UN identification number is 1340. The NFPA 704 designation is health 2, flammability 1, and reactivity 2. Primary uses are in insecticides, safety matches, ignition compounds, and sulfonation.
