Ethanol burns in air
3 marks · NormalExplain why burning ethanol as a fuel is considered more sustainable than burning petrol. Include reference to raw materials and renewability.
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Ethanol is more sustainable because it is made from renewable resources such as plants (sugar cane or corn), which can be regrown. Petrol comes from fossil fuels, which are non-renewable and take millions of years to form. Ethanol can be continually produced as long as crops are grown, while petrol sources will eventually run out.
Must show: Mentions ethanol is renewable/plant-based, Mentions petrol is non-renewable/fossil fuel, Explains why this makes ethanol more sustainable
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Marking points
B1 · 1 mark · Ethanol comes from renewable plants/biological sources.
B2 · 1 mark · Petrol is non-renewable/fossil source.
B3 · 1 mark · Explains that renewability means ethanol can be replaced/regrown, so is more sustainable.
Worked solution
Ethanol is made from crops like sugar cane, which can be regrown each year, making it renewable. Petrol is produced from crude oil, which takes millions of years to form and is non-renewable. Because ethanol's raw materials can be continually replaced, burning ethanol is considered more sustainable than using petrol.