09020 IUPAC Gold Book - Henry’s law constant 10.1351/goldbook.09020 09020 current 1 Proportionality factor describing the equilibrium distribution of a chemical species between the gas phase and a liquid solution at infinite dilution of the solute according to Henry’s law. It is an umbrella term for the reciprocal quantities Henry’s law solubility constant and Henry’s law volatility constant. Because of its ambiguity, it is strongly recommended to specify whether a solubility or volatility constant is intended. Henry’s law solubility constant https://goldbook.iupac.org//terms/view/09021 Henry’s law volatility constant https://goldbook.iupac.org//terms/view/09022 PAC, 2022, 94, 71. 'Henry’s law constants (IUPAC Recommendations 2021)' on page 75 (https://doi.org/10.1515/pac-2020-0302) https://goldbook.iupac.org/terms/view/09020/html https://goldbook.iupac.org/terms/view/09020/json https://goldbook.iupac.org/terms/view/09020/plain Citation: 'Henry’s law 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.09020 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-04-27T16:10:53+00:00