Title: binodal
Long Title: IUPAC Gold Book - binodal
DOI: 10.1351/goldbook.12240
Status: current

Definition
Curve in the isobaric temperature-composition plane for a mixture defining the region of composition and temperature across which a transition occurs from miscibility of the components to conditions where single-phase mixtures are metastable or unstable.

Note
Binodal compositions are defined by pairs of points on the curve defining the dependence of Gibbs energy of mixing on composition that have common tangents, corresponding to compositions of equal chemical potentials of each of the two components in two phases.

Source
- PAC, 2015, 87, 71. 'Definitions of terms relating to individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers (IUPAC Recommendations 2014)' on page 95 (https://doi.org/10.1515/pac-2013-0201)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/12240/html
- json: https://goldbook.iupac.org/terms/view/12240/json
- xml: https://goldbook.iupac.org/terms/view/12240/xml

Citation: Citation: 'binodal' 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.12240
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Accessed: 2026-07-26T18:03:50+00:00