Freons - Halogen Derivatives
The chloro fluoro that is derivatives of methane and ethane are called freons. Some of the derivatives are: CHF2Cl (monochlorodifluoromethane), CF2Cl2 (dichlorodifluoro-methane), HCF2CHCl2 (1,1-dichloro-2,2-difluoroethane).
The above derivatives are colourless, non-inflammable, low boiling liquids, non-toxic. These are constant upto 550°C. The very significant and helpful derivative is which is commonly termed as freon and freon-12.