Universal indicator

Rarity: Common

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At a glance

Class

Notion

Domain

Science and technology

In collections

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What Wikipedia says

A universal indicator is a pH indicator made of a solution of several compounds that exhibit various smooth colour changes over a wide range pH values to indicate the acidity or alkalinity of solutions. A universal indicator can be in paper form or present in a form of a solution.

Excerpt from the Wikipedia article “Universal indicator”, under the CC BY-SA 4.0 license. Read the article on Wikipedia

Image: Dejan Jovic DJ, CC BY-SA 4.0, via Wikimedia Commons.