Term: liquid junction
https://doi.org/10.1351/goldbook.L03584

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:
1) operational ph cell (http://doi.org/10.1351/goldbook.O04298).
2) filling solution (<em>of a reference electrode</em>) (http://doi.org/10.1351/goldbook.F02365).
3) bridge solution (<em>of a reference electrode</em>) (<em>in </em>ph<em> measurement</em>) (http://doi.org/10.1351/goldbook.B00740).
4) reference electrode (<em>of a reference electrode</em>) (<em>in </em>ph<em> measurement</em>) (http://doi.org/10.1351/goldbook.R05229).
5) ph standard (http://doi.org/10.1351/goldbook.P04661).

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)

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. https://doi.org/10.1351/goldbook.L03584

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