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Chemistry LibreTexts

Oxidation Number

  • Page ID
    40812
  • The oxidation number or oxidation state of an atom in a molecule or a polyatomic ion is the charge it would bear if all its bonds to unlike atoms were ionic bonds.

    eg. 1: Methane

    There are no bonds connecting like atoms in the methane molecule.
    electronegativity: C > H

    eg. 2: Acetaldehyde

    There is one bond connecting like atoms in the acetaldehyde molecule, the carbon-carbon bond.
    electronegativity: O > C > H

    eg. 3: Nitric acid

    There are no bonds connecting like atoms in the nitric acid molecule.
    electronegativity: O > N > H

    eg. 4: Periodate ion

    There are no bonds connecting like atoms in the periodate ion.
    electronegativity: O > I

    see also oxidation, reduction