oxidation state

noun, Chemistry
1.
the state of an element or ion in a compound with regard to the electrons gained or lost by the element or ion in the reaction that formed the compound, expressed as a positive or negative number indicating the ionic charge of the element or ion.
Also called oxidation number.
Origin
1945-50
Examples from the web for oxidation number
  • Reduction occurs when an atom undergoes a decrease in oxidation number.
  • Oxidation is accompanied by an increase in oxidation number on the atoms, molecules, or ions that lose electrons.
Contemporary definitions for oxidation number
noun

the degree of oxidaton of an atom or molecule, represented by a positive or negative number; the number of electrons theoretically gained or lost in converting an atom or molecule to its elemental form; also called oxidation state

Examples

The oxidation number is number of electrons necessary to restore an atom in a combined state to its elemental form.

oxidation number in Science
oxidation state  
See valence.
Encyclopedia Article for oxidation number

the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.

Learn more about oxidation number with a free trial on Britannica.com