CFCs and Ozone Depletion
AQA A-Level Chemistry
3.3.3
Having explored how free-radical substitution can be used to form halogenoalkanes, we can now consider how further substitution reactions can replace the remaining hydrogen atoms in a molecule to form chlorofluorocarbons (CFCs). We’ll then look at how CFCs were used, why they were eventually banned, and how chlorine free radicals catalyse the decomposition of ozone in the atmosphere. This brings our study of halogenoalkanes to a close before we move on to alkenes.
In this topic you will:
- Explain what CFCs are and how they are formed through further free-radical substitution.
- Understand why CFCs were widely used and why their use was eventually banned.
- Explain how CFCs cause the depletion of ozone in the atmosphere.
- Understand how chlorine free radicals act as catalysts in the decomposition of ozone.
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