Term: critical solution point
https://doi.org/10.1351/goldbook.C01400

Definition:
The point, with coordinates critical solution temperatures and critical composition, on a temperature-composition phase diagram at which the distinction between co-existent phases vanishes. In solid-solid, solid-liquid and liquid-liquid systems both upper and lower critical solution temperatures and corresponding critical solution compositions can occur. Synonymous with consolute point.

Related Terms:
1) critical solution temperatures (http://doi.org/10.1351/goldbook.C01401).
2) critical solution compositions (http://doi.org/10.1351/goldbook.C01399).

Source: PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 580 (https://doi.org/10.1351/pac199466030577)

Citation: 'critical solution point' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C01400

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