Title: Henry’s law solubility constant (via c and p)
Long Title: IUPAC Gold Book - Henry’s law solubility constant (via c and p)
DOI: 10.1351/goldbook.09024
Status: current

Definition
Amount concentration \(c_{\rm{l}}\) of a species in the liquid phase divided by the partial pressure \(p\) of that species in the gas phase under equilibrium conditions at infinite dilution: \[H_{\rm{s}}^{cp}: = \underset{c_{\rm{l}} \to 0}{\rm{lim}}\frac{c_{\rm{l}}}{p}\]

Note
The coherent SI unit for \(H_{\rm{s}}^{cp}\) is \(\pu{mol m-3 Pa-1}\). Another commonly used unit is \(\pu{mol L-1 bar-1}\), equivalent to \(\pu{10E-2 mol m-3 Pa-1}\).

Example
The Henry solubility of ozone in water at \(T = \pu{298.15 K}\) is \(H_{\rm{s}}^{cp}(\ce{O3}) = \pu{1.0E-4 mol m-3 Pa-1}\).

Related Term
- Henry’s law solubility constant: https://goldbook.iupac.org//terms/view/09021

Source
- PAC, 2022, 94, 71. 'Henry’s law constants (IUPAC Recommendations 2021)' on page 75 (https://doi.org/10.1515/pac-2020-0302)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/09024/html
- json: https://goldbook.iupac.org/terms/view/09024/json
- xml: https://goldbook.iupac.org/terms/view/09024/xml

Citation: Citation: 'Henry’s law solubility constant (via c and p)' 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.09024
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Accessed: 2026-04-27T16:09:10+00:00