# A student adds excess zinc carbonate powder to dilute hydrochloric acid. The mixture fizzes and eventually the fizzing stops. State and explain what the student would observe about the final mixture, and describe how the student could obtain a pure, dry sample of zinc chloride from this mixture.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 3.4 Acids, alkalis and salts · State, Explain and Describe · 4 marks

> Zinc carbonate reacts with hydrochloric acid to produce zinc chloride, water and carbon dioxide.

## Mark scheme (4 marks)

1. Unreacted / excess zinc carbonate remains visible (as a solid) in the final mixture
2. Zinc carbonate is in excess so the hydrochloric acid is completely used up / neutralised, leaving unreacted zinc carbonate
3. Filter the mixture to remove the excess zinc carbonate solid
4. Evaporate / heat the filtrate (zinc chloride solution) to obtain dry zinc chloride crystals

## Key terms

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

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](https://www.gradenine.co.uk/learn)
- [How to answer "State, Explain and Describe" 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-adds-excess-zinc-carbonate-2431a38c) · Published by Druglandscape Ltd.