Universal indicator

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.^[1]

^ Walker, Denise (2007). Acids and alkalis (1 ed.). London: Evans. p. 13. ISBN 978-0-237-53002-0. Retrieved 4 June 2015.

[1] Walker, Denise (2007). Acids and alkalis (1 ed.). London: Evans. p. 13. ISBN 978-0-237-53002-0. Retrieved 4 June 2015.

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