Term: basicity
https://doi.org/10.1351/goldbook.B00611

Definition:
For Brønsted bases, the tendency of a compound to act as hydron (proton) acceptor. The basicity of a chemical species is normally expressed by the acidity of the conjugate acid (see conjugate acid–base pair). For Lewis bases it relates to the association constants of Lewis adducts and π-adducts.

Related Terms:
1) brønsted bases (http://doi.org/10.1351/goldbook.B00745).
2) hydron (http://doi.org/10.1351/goldbook.H02904).
3) chemical species (http://doi.org/10.1351/goldbook.CT01038).
4) acidity (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.A00079).
5) conjugate acid–base pair (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.C01266).
6) lewis adducts (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.L03510).
7) π-adducts (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.A04388).
8) proton (http://doi.org/10.1351/goldbook.P04906).
9) association (<em>of a compound, of a medium</em>) (http://doi.org/10.1351/goldbook.A00472).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1088 (https://doi.org/10.1351/pac199466051077)

Citation: 'basicity' 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.B00611

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