Term: reference electrode
https://doi.org/10.1351/goldbook.R05229

Definition:
An external electrode system which comprises an inner element, usually mercury–mercury(I) chloride (calomel), silver–silver chloride or thallium amalgam–thallium(I) chloride, a chamber containing the appropriate filling solution and a device for forming a liquid junction, e.g. capillary, ceramic plug, fritted disc or ground glass sleeve.

Related Terms:
1) liquid junction (http://doi.org/10.1351/goldbook.L03584).
2) ceramic (http://doi.org/10.1351/goldbook.CT07540).

Source: Orange Book, 2nd ed., p. 27 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'reference electrode' 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.R05229

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