Atoms can give one or more electrons for bond forming. The valence of any atom, which comes from stechiometrical relation of interbonded atoms, is called an oxidation number or an oxidation degree. Oxidation number of atoms in elementary state is zero. An atom of greater electronegativity has a negative, and an atom of lesser electronegativity has a positive oxidation number.
Generalic, Eni. "Oxidation number." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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