5.4 Halogen Derivatives Halogeno Compounds LO: I know a variety of uses for halogeno compounds

trichloromethane (chloroform) NAMESTRUCTUREUSE anaesthetic 1,1,1-trichloroethanesolvent chloroethene (vinylchloride) manufacture of PVC tetrafluoroethene manufacture of Teflon LO: I know a variety of uses for halogeno compounds

5.4.2 Chlorofluorocarbons LO: I understand the structure and properties of CFCs

Chlorofluorocarbons are based on alkane molecules where the hydrogens have been replaced by a mixture of chlorine and fluorine. dichlorodifluoromethane neutral insoluble unreactive non-flammable easily liquefied long lastingpropellant refrigerant LO: I understand the structure and properties of CFCs

CFCs were used as refrigerants instead of ammonia and sulphur dioxide which are. CFCs were used as propellants instead of propane and as they were not as dangerous (non- flammable). The use of CFCs was banned when it was discovered that they destroy. LO: I understand the structure and properties of CFCs toxic butane ozone

5.4.3 Ozone LO: I understand how CFCs cause a problem for the ozone layer.

Ozone provides a protective layer around the Earth against the damaging effects of radiation. UV radiation for the sun is responsible for the formation of in the upper atmosphere: O2O2 uv OO+ O2O2 O3O3 O+ UV radiation also splits CFCs in the upper atmosphere to produce atoms. Chlorine atoms react with, destroying it. LO: I understand how CFCs cause a problem for the ozone layer. (ozone) uv ozone chlorine ozone