Dichloromethane( CH2Cl2) is widely used as a solvent, as a propellant in aerosols. Direct contact of dichloromethane in humans causes intense burning and milk redness of the skin.
Trihalogen Derivatives 1. Chloroform [ Trichloromethane, CHCl 3 ] Methods of preparation
Properties 1. Oxidation of CHCl 3 gives poisonous gas phosgene( carbonyl chloride).
To avoid this oxidation CHCl 3 iI. toreci in dark brown bottles and filled to the brim. 1 % ethanol is added to chloroform which converts harmful phosgene gas into diethyl carbonate.
2. CHCl 3 is widely used in the production of freon refrigerant R-22.
3. On nitration, it gives tear producing insecticide substance chloropicrin.