Title: Donnan emf
Long Title: IUPAC Gold Book - Donnan emf
DOI: 10.1351/goldbook.D01830
Status: current

Definition
The potential difference \(E_{\rm{D}}\) at zero electric current between two identical salt bridges, usually saturated $\ce{KCl}$ bridges (conveniently measured by linking them to two identical electrodes) inserted into two solutions in Donnan equilibrium.

Related Terms
- Donnan equilibrium: https://goldbook.iupac.org//terms/view/D01831
- electric current: https://goldbook.iupac.org//terms/view/E01927
- salt: https://goldbook.iupac.org//terms/view/S05447

Source
- PAC, 1972, 31, 577. 'Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry' on page 619 (https://doi.org/10.1351/pac197231040577)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/D01830/html
- json: https://goldbook.iupac.org/terms/view/D01830/json
- xml: https://goldbook.iupac.org/terms/view/D01830/xml

Citation: Citation: 'Donnan emf' 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.D01830
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Accessed: 2026-02-11T07:39:22+00:00