# Zinc nitrate has the formula Zn(NO₃)₂. When zinc nitrate is heated, it decomposes to form zinc oxide, nitrogen dioxide and oxygen. The word equation for this reaction is: zinc nitrate → zinc oxide + nitrogen dioxide + oxygen. Write the balanced symbol equation for this reaction, showing all state symbols at room temperature. The formula for nitrogen dioxide is NO₂ and the formula for zinc oxide is ZnO.

> Pearson Edexcel International GCSE Chemistry (4CH1) — 1.5 Chemical formulae, equations and calculations · State · 4 marks

## Mark scheme (4 marks)

1. Correct unbalanced formulae used: Zn(NO₃)₂ → ZnO + NO₂ + O₂
2. Correctly balanced equation: 2Zn(NO₃)₂ → 2ZnO + 4NO₂ + O₂
3. Correct state symbols for reactant and solid product: (s) for Zn(NO₃)₂ and ZnO
4. Correct state symbols for gaseous products: (g) for NO₂ and (g) for O₂

## Key terms

- [balanced symbol equation](https://www.gradenine.co.uk/glossary/balanced-symbol-equation)
- [state symbols](https://www.gradenine.co.uk/glossary/state-symbols)

## Related

- [Revision notes for Pearson Edexcel International GCSE Chemistry (4CH1)](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)

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Source: [GradeNine](https://www.gradenine.co.uk/q/zinc-nitrate-has-the-formula-zn-no-1fc14f44) · Published by Druglandscape Ltd.