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Carbon monoxide from transport fuels
Transport is a source of atmospheric pollutants.
Describe how carbon monoxide can be produced by transport.
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Marking points
- 1 States that fuel is burnt.
- 2 Explains that there is insufficient oxygen or that combustion is incomplete.
Full-mark answer
Transport fuels are burned. If there is insufficient oxygen, incomplete combustion occurs and carbon monoxide is produced.
Why this answer loses marks
Burning fuel produces carbon monoxide.
This names the product but not the necessary condition: insufficient oxygen makes the combustion incomplete.