Henry’s law constants

Provisional Recommendations are drafts of IUPAC recommendations on terminology, nomenclature, and symbols, made widely available to allow interested parties to comment before the recommendations are finally revised and published in IUPAC’s journal Pure and Applied Chemistry.


Abstract: Henry’s law states that the abundance of a volatile solute dissolved in a liquid is proportional to its abundance in the gas phase. It applies at equilibrium and in the limit of infinite dilution of the solute. For historical reasons, numerous different definitions, names, and symbols are used in the literature to express the proportionality coefficient, denoted the “Henry’s law constant”. Here, a consistent set of recommendations is presented. An important distinction is made between two new recommended reciprocal quantities “Henry’s law solubility constant” (Hs) and “Henry’s law volatility constant” (Hv). Eight recommended variants of Hs and Hv are described and relations among them presented.

Keywords: Henry’s law, solubility, volatility, gas-solution equilibrium

Access full text – return comments to the corresponding author Rolf Sander rolf.sander@mpic.de

Comments by 31 May 2021

See all  Provisional Recommendations currently under review.