Term: transition interval
https://doi.org/10.1351/goldbook.T06457

Definition:
The range of concentration over which the eye is able to perceive change in hue, colour intensity, fluorescence or other property of a visual indicator arising from the varying ratio of the two relevant forms of the indicator.

Related Terms:
1) fluorescence (http://doi.org/10.1351/goldbook.F02453).

Source: Orange Book, 2nd ed., p. 48 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'transition interval' 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.T06457

License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.

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