# Magnesium oxide is an ionic compound. Explain why magnesium oxide has a high melting point.

> Cambridge International IGCSE Chemistry (0620) — 2.4 Ions and ionic bonds · Explain · 4 marks

> Magnesium oxide is used to line the inside of furnaces because it can withstand very high temperatures without melting.

## Mark scheme (4 marks)

1. Magnesium oxide consists of oppositely charged ions (Mg²⁺ and O²⁻)
2. There are strong electrostatic forces of attraction between the oppositely charged ions
3. A large amount of energy is needed to overcome these forces / break these bonds
4. The ions are held in a giant ionic lattice / structure

## Key terms

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

## Related

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