# Ionic compounds such as sodium chloride do not conduct electricity when solid, but they do conduct electricity when melted or dissolved in water. Explain why ionic compounds behave in this way.

> Eduqas GCSE Chemistry — C2 Bonding, structure and properties · Explain · 4 marks

## Mark scheme (4 marks)

1. In the solid state, the ions are fixed in place (in a lattice) and cannot move
2. Because the ions cannot move, charge cannot be carried, so solid ionic compounds do not conduct electricity
3. When melted or dissolved, the ions are free to move
4. The free-moving ions can carry electrical charge, so the compound conducts electricity

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/ionic-compounds-such-as-sodium-chloride-d3931717) · Published by Druglandscape Ltd.