Illustrated Glossary of Organic Chemistry

Chlorofluorocarbon (CFC): A molecule containing only chlorine, fluorine, and carbon. Used as refrigerants, propellants, and blowing agents, but now banned internationally by the Montreal Protocol. Connected with annual ozone holes over the Earth's Antarctic and Arctic regions. HCFCs (hydrofluorochlorocarbons) were initially used to replace CFCs in many applications, because it was thought these molecules would degrade in the atmosphere before reaching the ozone layer. However recent studies suggest that HCFCs may also lead to ozone depletion. HCFCs are now being replaced by hydrofluorocarbons (HFCs).

Dichlorodifluoromethane (Freon-12),
a typical chlorofluorocarbon (CFC).
1,1-Dichloro-1-fluoroethane (HCFC-141b),
a typical hydrochlorofluorocarbon (HCFC).
1,1-Difluoroethane (HFC-152a),
a typical hydrofluorocarbon (HFC).