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
Public review ended 31 May 2021
IUPAC Recommendations published in PAC AOP 13 Dec 2021