# Sodium chloride is an ionic compound. Explain why solid sodium chloride does not conduct electricity, but sodium chloride dissolved in water does conduct electricity.

> OCR A-Level Chemistry B: Salters (H433) — 2.4 Electrons, bonding and structure · Explain · 5 marks

> Sodium chloride is widely used in the food industry and in industrial chemical processes. It is composed of sodium ions and chloride ions held together by strong electrostatic forces.

## Mark scheme (5 marks)

1. In solid sodium chloride, the ions are held in fixed positions (in a lattice) by strong electrostatic forces
2. Because the ions cannot move, no charge can be carried / no current can flow
3. When sodium chloride dissolves in water, the ions separate / become free to move
4. The free-moving ions can carry charge through the solution
5. The strong electrostatic forces between oppositely charged ions are overcome / broken down when the compound dissolves

## Key terms

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

## Related

- [Revision notes for OCR A-Level Chemistry B: Salters (H433)](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/sodium-chloride-is-an-ionic-compound-d924fa7b) · Published by Druglandscape Ltd.