Uses of Freon − 12
Freon-12 (dichlorodifluoromethane, CF${}_2$Cl${}_2$) is commonly known as CFC. It is used as a
refrigerant in refrigerators and air conditioners. It is also used in aerosol spray propellants
such as body sprays, hair sprays, etc. However, it damages the ozone layer. Hence, its
manufacture was banned in the United States and many other countries in 1994.
Uses of DDT
DDT (p, p−dichlorodiphenyltrichloroethane) is one of the best known insecticides. It is very
effective against mosquitoes and lice. But due its harmful effects, it was banned in the
United States in 1973.
Uses of carbontetrachloride (CCl${}_4$)
(i) It is used for manufacturing refrigerants and propellants for aerosol cans.
(ii) It is used as feedstock in the synthesis of chlorofluorocarbons and other chemicals.
(iii) It is used as a solvent in the manufacture of pharmaceutical products.
(iv) Until the mid 1960’s, carbon tetrachloride was widely used as a cleaning fluid, a
degreasing agent in industries, a spot reamer in homes, and a fire extinguisher.

Uses of iodoform (CHI${}_3$)
Iodoform was used earlier as an antiseptic, but now it has been replaced by other
formulations-containing iodine-due to its objectionable smell. The antiseptic property of
iodoform is only due to the liberation of free iodine when it comes in contact with the skin.