2. Learning objectives Outline the uses of chloroethene and tetrafluoroethene in the production of the plastics PVC and PTFE. Explain why CFCs were first developed and their subsequent effect on the ozone layer. Outline the role of ‘green’ chemistry in minimising damage to the environment by promoting alternatives to CFCs.

3. Halogen containing polymers How are chloroethene (C 2 H 3 Cl) and tetrafluoroethene used to produce PVC and PTFE? Draw and name the monomer and polymer of chloroethene and tetrafluoroethene. Uni-structural

4. Halogen containing polymers Multi-structural Information on PVC and PTFE List the uses of PTFE and PVC. What properties do they have that make them suitable for their uses? What influences these properties?

5. Halogen containing polymers Who was Thomas Midgely? What chemical did he discover? Multi-structural

6. Chlorofluorocarbons A Short History of Nearly Everything Chapter 10 (podcast?)

7. Chlorofluorocarbons Explain what happens to the CFCs in the stratosphere? Scroll down the page!

8. Trouble with CFCs What impact did the use of CFCs have on the ozone layer?

9. Trouble with CFCs What is ozone?

10. Alternatives to CFCs Information on HCFCs A good general page of information

11. Questions On the wiki – complete for homework