Title: fugacity coefficient
Long Title: IUPAC Gold Book - fugacity coefficient
DOI: 10.1351/goldbook.F02544
Status: current
Index: quantity

Definition
Ratio of fugacity to the partial pressure of a gaseous constituent.

Related Terms
- constituent: https://goldbook.iupac.org//terms/view/C01281
- fugacity: https://goldbook.iupac.org//terms/view/F02543
- partial pressure: https://goldbook.iupac.org//terms/view/P04420

Sources
- Green Book, 2nd ed., p. 50 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)
- PAC, 1994, 66, 533. 'Standard quantities in chemical thermodynamics. Fugacities, activities and equilibrium constants for pure and mixed phases (IUPAC Recommendations 1994)' on page 539 (https://doi.org/10.1351/pac199466030533)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/F02544/html
- json: https://goldbook.iupac.org/terms/view/F02544/json
- xml: https://goldbook.iupac.org/terms/view/F02544/xml

Citation: Citation: 'fugacity coefficient' 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.F02544
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Accessed: 2026-07-02T18:25:18+00:00