# A student wants to investigate whether the surface area of wood affects how quickly it burns in air. Describe how the student could carry out a fair test to investigate this.

> Cambridge International IGCSE Chemistry (0620) — 12.1 Experimental design · Describe · 4 marks

> The student has access to wooden blocks and wooden chips of the same type of wood, a balance, a stopwatch, and a heat source.

## Mark scheme (4 marks)

1. Keep the mass (or volume) of wood the same in each experiment
2. Use the same type / species of wood throughout
3. Measure a variable to determine how quickly the wood burns, e.g. time taken for the wood to fully burn / time for the flame to go out / mass lost per unit time
4. Compare two different surface areas, e.g. one large block versus small chips, whilst keeping all other variables (heat source, surrounding air supply) the same

## Key terms

- [fair test](https://www.gradenine.co.uk/glossary/fair-test)
- [surface area](https://www.gradenine.co.uk/glossary/surface-area)

## Related

- [Revision notes for Cambridge International IGCSE Chemistry (0620)](https://www.gradenine.co.uk/learn)
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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-wants-to-investigate-whether-d3aeef0b) · Published by Druglandscape Ltd.