# Magnesium reacts with oxygen to form magnesium oxide. Explain, in terms of electrons, what happens to the magnesium and oxygen atoms during this reaction, and state the type of bonding present in magnesium oxide.

> Edexcel A-Level Chemistry (9CH0) — Topic 1 Foundations in chemistry · Explain · 5 marks

> Magnesium burns in oxygen to form a white solid, magnesium oxide. The formula of magnesium oxide is MgO.

## Mark scheme (5 marks)

1. Magnesium atom loses 2 electrons (to form Mg²⁺ ion)
2. Oxygen atom gains 2 electrons (to form O²⁻ ion)
3. Both ions formed have a full outer shell / achieve a stable electron configuration
4. Oppositely charged ions are formed (Mg²⁺ and O²⁻)
5. The type of bonding in magnesium oxide is ionic bonding

## Key terms

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

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Source: [GradeNine](https://www.gradenine.co.uk/q/magnesium-reacts-with-oxygen-to-form-4359049f) · Published by Druglandscape Ltd.