Cracking Hydrocarbons
AQA A-Level Chemistry
3.3.2
The fractions obtained from crude oil contain hydrocarbons of different sizes, but the demand for smaller hydrocarbons is greater than the amounts that can be obtained directly from crude oil. Building on the understanding of fractional distillation, we can now explore how cracking hydrocarbons converts larger molecules into smaller, more useful ones. This introduces both thermal and catalytic cracking, and provides a useful link to the wider range of hydrocarbons and reactions encountered later in organic chemistry.
In this topic you will:
- Understand why the oil industry uses cracking to convert large hydrocarbons into smaller, more useful molecules.
- Explore how cracking rearranges atoms to produce a mixture of different hydrocarbon products, including alkanes and alkenes.
- Learn how thermal and catalytic cracking work, and how different conditions influence the products formed.
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