Term: acidity
https://doi.org/10.1351/goldbook.A00079

Definition:
For Brønsted acids the tendency of a compound to act as a hydron donor. It can be quantitatively expressed by the acid dissociation constant of the compound in water or some other specified medium. For Lewis acids it relates to the association constants of Lewis adducts and π adducts.

Related Terms:
1) brønsted acids (http://doi.org/10.1351/goldbook.B00744).
2) hydron (http://doi.org/10.1351/goldbook.H02904).
3) lewis acids (http://doi.org/10.1351/goldbook.L03508).
4) lewis adducts (http://doi.org/10.1351/goldbook.L03510).
5) π adducts (http://doi.org/10.1351/goldbook.A04388).
6) dissociation (http://doi.org/10.1351/goldbook.D01801).
7) association (http://doi.org/10.1351/goldbook.A00472).

Source: 

Citation: 'acidity' 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.A00079

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