CAIE A Level Chemistry 9701 · Polymerisation
A sample of PVC, poly(chloroethene), is burned in an open fire along with other household waste.
Describe the addition polymerisation of chloroethene to form PVC, and explain why the combustion of PVC in this way is more harmful to the environment than the combustion of poly(ethene).
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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