Term: oxidation number
https://doi.org/10.1351/goldbook.O04363

Definition:
In English is largely synonymous with oxidation state, and may be preferred when the value represents a mere parameter or number rather than being related to chemical systematics or a state of the atom in a compound. Etymologically, it stems from the no-longer-used term Stock number (oxidation number of a central atom; the charge it would bear if all the ligands were removed along with the electron pairs that were shared with the central atom) and the likewise obsolete term Ewens–Bassett number (ion charge).

Related Terms:
1) oxidation state (http://doi.org/10.1351/goldbook.O04365).
2) stock number (http://doi.org/10.1351/goldbook.S06020).
3) central atom (http://doi.org/10.1351/goldbook.C00930).
4) ewens–bassett number (http://doi.org/10.1351/goldbook.E02231).

Source: PAC, 2014, 86, 1017. 'Toward a Comprehensive Definition of Oxidation State' on page 1020-1021 (https://doi.org/10.1515/pac-2013-0505)

Citation: 'oxidation number' 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.O04363

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