Title: standard thermodynamic quantities
Long Title: IUPAC Gold Book - standard thermodynamic quantities
DOI: 10.1351/goldbook.S05927
Status: current

Definition
Values of thermodynamic functions in the standard state characterized by a standard pressure, molality or amount concentration, but not by temperature. Standard quantities are denoted by adding the superscript \(^{⦵}\) or \(^{\circ}\) to the symbol of the quantity.

Related Terms
- amount concentration: https://goldbook.iupac.org//terms/view/A00295
- standard pressure: https://goldbook.iupac.org//terms/view/S05921
- standard state: https://goldbook.iupac.org//terms/view/S05925

Source
- Green Book, 2nd ed., p. 53 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Related Reference
- PAC, 1994, 66, 533. 'Standard quantities in chemical thermodynamics. Fugacities, activities and equilibrium constants for pure and mixed phases (IUPAC Recommendations 1994)' on page 536 (https://doi.org/10.1351/pac199466030533)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/S05927/html
- json: https://goldbook.iupac.org/terms/view/S05927/json
- xml: https://goldbook.iupac.org/terms/view/S05927/xml

Citation: Citation: 'standard thermodynamic quantities' 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.S05927
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Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-06-12T11:51:18+00:00