# A student heats iron filings and sulfur powder together. After heating, a new grey solid is formed that cannot be separated by using a magnet. Explain why the product formed is a compound and not a mixture.

> Cambridge International IGCSE Chemistry (0620) — 2.1 Elements, compounds and mixtures · Explain · 4 marks

> Iron and sulfur can be mixed together or chemically combined to form different materials.

## Mark scheme (4 marks)

1. In the compound, the iron and sulfur are chemically combined / joined by chemical bonds
2. The compound has fixed / definite proportions of iron and sulfur (by mass)
3. The compound has different properties from the elements that formed it / the original iron and sulfur
4. The elements cannot be separated by physical methods (e.g. a magnet / filtration) / can only be separated by a chemical reaction

## Key terms

- [compound](https://www.gradenine.co.uk/glossary/compound)
- [mixture](https://www.gradenine.co.uk/glossary/mixture)

## Related

- [Revision notes for Cambridge International IGCSE Chemistry (0620)](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/a-student-heats-iron-filings-and-66b86399) · Published by Druglandscape Ltd.