# hydroxide

/haɪˈdɹɑksaɪd/ (US) · /haɪdɹˈɒksaɪd/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/hydroxide
Updated: 2026-05-19

## Definition

a chemical compound that contains the group OH⁻. You often find this in cleaning products or when water reacts with certain metals.

For teachers: a chemical compound containing the hydroxide ion, OH⁻. It is typically formed when a base reacts with water or when a metal reacts with water.

## Examples

- Sodium hydroxide is a common ingredient in soap.
- When aluminum reacts with water, it produces aluminum hydroxide and hydrogen gas.
- The formation of magnesium hydroxide in the soil helps to neutralize acidic conditions, making the environment more hospitable for plant life.

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