Article: Chloropicrin

Chloropicrin
Discovery
Discovered by	?
Discovered in	?
Chemical characteristics
Chemical name	Trichloronitromethane
Chemical family	?
Chemical formula	CCl3NO2
CAS number	76-06-2
Boiling point	112 °C (234 °F)
Freezing/melting point	-69.2 °C (-92.6 °F)
Vapor pressure	? mmHg (? Pa) at 25 °C
Vapor relative density (air=1)	?
Solubility in water	?
Density at 25 °C	? g/cm3
Appearance and color	Colorless / faint yellow

Chloropicrin is a slightly oily, colorless or faintly yellow liquid of the formula CCl₃NO₂. Its freezing point is -69.2 °C and its boiling point is 112 °C, where it partially decomposes to phosgene and nitrosyl chloride. It is denser than water. It is more toxic than chlorine but less than phosgene. Its CAS number is [76-06-2][1].

Chloropicrin vapor is highly poisonous if inhaled. Chloropicrin was used in World War I as a chemical weapon, called PS by British, Aquinite by French, and Klop (green cross) by Germans. See also Use of poison gas in World War I. After WW II, however, the importance of Chloropicrin for military use decreased and, today, has vanished. In the chemical industry, it is widely used for organic synthesis, in fumigants, in fungicides and insecticides, and for the extermination of rats. Chloropicrin is a relatively stable liquid that is prepared by the reaction of picric acid with calcium hypochlorite, by the addition of nitrogen to chlorinated hydrocarbons, or by chlorinating nitromethane. In environment it undergoes photolysis.

Chloropicrin is used for fumigation, to sterilize soil and seed.

As a chemical warfare agent it is a powerful irritant from the group of pulmonary agents. It causes lachrymation, vomiting, bronchitis, and pulmonary edema; the lung injury can be fatal. Very low concentrations cause burning sensation of the eyes, which may serve as a warning. Because of its relative inertness and the small size of its molecule, chloropicrin penetrates gas mask filters. It then causes vomiting, which makes the victim remove the gas mask. For this reason, it is often mixed with other chemical weapons.