activity (relative activity), a

https://doi.org/10.1351/goldbook.A00115
Defined by the equation a=eμ−μoRT where R is the gas constant, T the thermodynamic temperature, μ the chemical potential and μo the standard chemical potential the definition of which depends on the choice of the standard state.
See also: absolute activity
Sources:
Green Book, 2nd ed., p. 49 [Terms] [Book]
PAC, 1996, 68, 957. (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 989 [Terms] [Paper]
Citation: 'activity' 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.A00115 RIS BibTex EndNote
Div. IDiv. VIIPDFTextXMLJSONQuantity