Shells, chemical phosgene

When phosgene (Cl2C=0 dichloromethanone) was used as a weapon to gas troops in World War I, it was delivered in shells that exploded on contact and released the chemical. Phosgene is a colorless gas, but when the shell exploded a cloud of whitish gas soon appeared. Comment on what happened to the phosgene to cause this. 

Fig. 1.31 From left to right a Livens container (phosgene), a 4 Stokes (Mortar Bomb (chloropicrin) and a 6" shell (mustard gas), found buried at Bramley in 1987 (reproduced with permission of the Chemical Defence Establishment, Porton Down). They all exhibit an advanced state of corrosion.

Fig. 2-18. The chemical weapons of the 1920s and 1930s. From left to right the 75-mm mustard shell the 4.2-in. white phosphorus shell the Ml 30 lb mustard bomb the Mk II 155-mm mustard shell the Livens phosgene projectile and the Mk I portable chemical cylinder. Photograph Chemical and Biological Defense Command Historical Research and Response Team, Aberdeen Proving Ground, Md.

A 1923 list sets the war reserve CWM at, White Phosphorus 500 tons. Titanium tetrachloride 100 tons. Phosgene 192 tons, Mustard Gas 60 tons. Chlorine 200 tons, Chlorpicrin 40 tons. .. Shell 4 Stokes Mortar, complete 188,000, Livens Projectors 25,000, Shell, L.P. complete 40,000, Cylinders, chemical, portable 25,000, Candles, smoke 75,000, Candles, toxic 15,000, Candles, lachrymatory 25,000, Arsenious oxide 100 tons. .. Sulphur monochloride 2,000 tons. .. Hexochlorethane 100 tons. While this is substantial and frightening, it is considerably less than the material known to have been on hand at the end of the war, particularly the shells and smoke candles. The author believes that the balance was buried or dumped at sea during the years following World War I. 

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