Chloroform

Chloroform, also called trichloromethane (CHCl3), is a colourless liquid with a distinctive, peculiar sweet smell. It is used to prepare chlorofluoromethane, the refrigerant known as R-22, and as a solvent for extracting natural products such as gums, fats and resins from plant or animal material; it is also used in the laboratory as a source of dichlorocarbene, a reactive divalent carbon species (this is the fact tested directly in Exercise 1.x of this chapter). Chloroform causes depression of the central nervous system: inhaling it even for a short time causes fatigue, dizziness and headache, and long-term exposure may affect the liver. A particular storage hazard is that chloroform, when exposed to air and light, slowly reacts to form phosgene, a highly poisonous gas -- for this reason chloroform is alwa …