Term: halochromism
https://doi.org/10.1351/goldbook.H02725

Definition:
The colour change which occurs on addition of acid (or base, or a salt) to a solution of a compound. A chemical reaction (e.g. ion formation) transforms a colourless compound into a coloured one.

Related Terms:
1) acid (http://doi.org/10.1351/goldbook.A00071).
2) base (http://doi.org/10.1351/goldbook.B00601).
3) salt (http://doi.org/10.1351/goldbook.S05447).
4) chemical reaction (http://doi.org/10.1351/goldbook.C01033).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1119 (https://doi.org/10.1351/pac199466051077)

Citation: 'halochromism' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.H02725

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