Title: liquid junction
Long Title: IUPAC Gold Book - liquid junction
DOI: 10.1351/goldbook.L03584
Status: current

Definition
Any junction between two electrolyte solutions of different composition. Across such a junction there arises a potential difference, called the liquid junction potential. In the operational pH cell the junction is between the test, or pH standard, solution and the filling solution or the bridge solution of the reference electrode.

Related Terms
- bridge solution: https://goldbook.iupac.org/terms/view/B00740
- filling solution: https://goldbook.iupac.org/terms/view/F02365
- operational pH cell: https://goldbook.iupac.org/terms/view/O04298
- pH standard: https://goldbook.iupac.org/terms/view/P04661
- reference electrode: https://goldbook.iupac.org/terms/view/R05229

Source
- PAC, 1985, 57, 531. 'Definition of pH scales, standard reference values, measurement of pH and related terminology (Recommendations 1984)' on page 541 (https://doi.org/10.1351/pac198557030531)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/L03584/html
- json: https://goldbook.iupac.org/terms/view/L03584/json
- xml: https://goldbook.iupac.org/terms/view/L03584/xml

Citation: Citation: 'liquid junction' 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.L03584
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Accessed: 2026-06-24T19:17:16+00:00