Title: solubility constant
Long Title: IUPAC Gold Book - solubility constant
DOI: 10.1351/goldbook.15359
Status: current

Definition
Generalization of solubility product to include, for example, undissociated salt or uncharged cation-anion pair as solute, reaction between solution species and the cation or anion of the solid salt, and gas-solution equilibria.

Note
The solubility constant can also be considered in many cases as relating to a solubility equilibrium as described under solubility product plus one or more simultaneous homogeneous equilibria in solution.

Source
- PAC, 2008, 80, 233. 'Glossary of terms related to solubility (IUPAC Recommendations 2008)' on page 264 (https://doi.org/10.1351/pac200880020233)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/15359/html
- json: https://goldbook.iupac.org/terms/view/15359/json
- xml: https://goldbook.iupac.org/terms/view/15359/xml

Citation: Citation: 'solubility constant' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.15359
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Accessed: 2026-06-28T18:51:29+00:00