Freon-12 is used as domestic coolents. Its chemical formula is CCl2F2. It is non-reactable, stable & easily liquifiable gas. It is used in Aerosol propellant, refrigerant A.C. It breaks Ozone & release Nascent oxygen, which break (Nascent oxygen) million of Ozone. So it deplete the ozone layer. CCl2F2+O3→CClF2+ClO+O2O3→O2+[0] (Nascent oxygen). In this way, freon destroys ozone by affecting its equilibrium.