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Oxidation Number

  • Page ID
    40812
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    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

    oxidationnumber1.png

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

    oxidationnumber2.png

    eg. 2: Acetaldehyde

    oxidationnumber3.png

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

    oxidationnumber4.png

    eg. 3: Nitric acid

    oxidationnumber5.png

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

    oxidationnumber6.png

    eg. 4: Periodate ion

    oxidationnumber7.png

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

    oxidationnumber8.png

    see also oxidation, reduction


    This page titled Oxidation Number is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Gamini Gunawardena via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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