CFCs (Chlorofluorocarbons)
Definition and meaning of CFCs (Chlorofluorocarbons) in chemistry.
CFCs (chlorofluorocarbons) are synthetic organic compounds made only of carbon, chlorine, and fluorine atoms, historically used as refrigerants, aerosol propellants, and industrial solvents.
In more detail
CFCs are volatile, chemically inert, and nontoxic under normal conditions, which made them ideal working fluids for refrigeration and air conditioning. Their very stability is the problem: because they resist breakdown in the lower atmosphere, CFC molecules persist long enough to drift into the stratosphere, where intense ultraviolet radiation breaks the carbon-chlorine bond, releasing free chlorine radicals. Each chlorine radical can catalytically destroy thousands of ozone (O3) molecules through repeated reaction cycles, contributing to stratospheric ozone depletion. Because of this, the 1987 Montreal Protocol phased out CFC production worldwide, replacing them with less damaging alternatives such as HFCs.
Key facts
| Field | Organic Chemistry |
|---|---|
| Composition | C, Cl, and F atoms only |
| Common example formula | CCl2F2 (CFC-12) |
| Environmental role | Catalyzes stratospheric ozone (O3) destruction via UV-generated Cl radicals |
Dichlorodifluoromethane, CCl2F2 (also called Freon-12 or R-12), was widely used as a refrigerant in older air conditioners and refrigerators before the Montreal Protocol phase-out.
Frequently asked questions
Why are CFCs harmful to the ozone layer?
UV radiation in the stratosphere breaks the weak carbon-chlorine bond in CFCs, releasing chlorine radicals that catalytically decompose ozone molecules, with each radical destroying many thousands of O3 molecules before it is removed from the cycle.
What replaced CFCs?
Hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) replaced CFCs after the Montreal Protocol, since HFCs contain no chlorine and cannot destroy ozone, though some HFCs are still potent greenhouse gases.