Term: radioactive equilibrium
https://doi.org/10.1351/goldbook.R05084

Definition:
Among the members of a decay chain, the state which prevails when the ratios between the activities of successive members remain constant. (This is not an equilibrium in the strict sense since radioactive decay is an irreversible process).

Related Terms:
1) decay chain (http://doi.org/10.1351/goldbook.D01537).
2) activities (<em>of a radioactive material</em>) (http://doi.org/10.1351/goldbook.A00114).
3) radioactive decay (<em>of a radioactive material</em>) (http://doi.org/10.1351/goldbook.R05083).

Source: PAC, 1994, 66, 2513. 'Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)' on page 2519 (https://doi.org/10.1351/pac199466122513)

Citation: 'radioactive equilibrium' 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.R05084

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