# alkali

/ˈæɫkəˌɫaɪ/ (US) · /ˈælkəlˌaɪ/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/alkali
Updated: 2026-05-18

## Definition

a substance that can neutralize an acid. It is usually a base that can react with acids to form salt and water.

For teachers: a substance that can neutralize an acid, typically a base that reacts with acids to form a salt and water. In a broader sense, it refers to any base or a solution containing one.

## Examples

- Lemon juice is an acid, while baking soda is an alkali.
- The soil was too acidic for the crops, so the farmer added lime, a natural alkali, to balance the pH.
- In the laboratory, the technician carefully measured the alkali to ensure the neutralization reaction occurred without producing excessive heat or gas.

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