# State two signs that a sample of water is not pure, and for each sign, identify the dissolved substance or type of contamination responsible.

> Cambridge International IGCSE Chemistry (0620) — 10.1 Water · State · 4 marks

## Mark scheme (4 marks)

1. Sign 1: the water has a colour / is coloured / is discoloured / is not clear / is turbid
2. Cause of sign 1: dissolved minerals / suspended particles / sediment / organic matter / heavy metal ions
3. Sign 2: the water has an unpleasant smell / odour / taste (different from sign 1)
4. Cause of sign 2: dissolved gases / microorganisms / sewage / pollutants / chlorine / hydrogen sulfide

## Key terms

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

## Related

- [Revision notes for Cambridge International IGCSE Chemistry (0620)](https://www.gradenine.co.uk/learn)
- [How to answer "State" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/state-two-signs-that-a-sample-c1387681) · Published by Druglandscape Ltd.