# Crude oil is a finite resource that is separated into fractions by fractional distillation. Explain why crude oil is described as a finite resource and outline two environmental problems caused by the combustion of hydrocarbon fuels obtained from crude oil.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 4.1 Introduction · Explain · 4 marks

## Mark scheme (4 marks)

1. Crude oil is a finite resource because it will one day run out / it cannot be replaced / it took millions of years to form
2. Complete combustion produces carbon dioxide, which contributes to the greenhouse effect / global warming / climate change
3. Combustion of hydrocarbons containing sulfur impurities produces sulfur dioxide, which causes acid rain
4. Incomplete combustion produces carbon particulates / carbon monoxide, which cause global dimming / health problems / are toxic

## Key terms

- [finite resource](https://www.gradenine.co.uk/glossary/finite-resource)
- [combustion](https://www.gradenine.co.uk/glossary/combustion)

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/crude-oil-is-a-finite-resource-bd2e6336) · Published by Druglandscape Ltd.