Phosgene

Phosgene, COCl2, is a colourless, reactive and very poisonous gas.

It is used in the production of polyurethane and smaller amounts of phosgene is used
in herbicides. 

The gas was used during World War I as a feared war gas.

Properties

Molecular weight   98.92 g/mol

Solid phase   Melting point: -118 °C

Liquid phase   Boiling point: 8.3 °C