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Oxidation

  • Page ID
    40811
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    1. If, in a reaction, the oxidation number of an atom in a reactant increases, the atom is said to undergo oxidation.

    eg. 1:

    oxidation1.png

    eg. 2:

    oxidation2.png

    eg. 3:

    oxidation3.png

    eg. 4:

    oxidation4.png

    2. If, in a species subjected to a reaction, the sum of oxidation numbers of atoms that participate in the overall reaction increases, the species is said to undergo oxidation.

    eg. 1:

    oxidation5.png

    In 1, the sum of oxidation numbers of atoms that participate in the reaction increases from -1 to +1; 1 is oxidized.

    eg. 2:

    oxidation6.png

    In 2, the sum of oxidation numbers of atoms that participate in the reaction increases from -3 to -1; 2 is oxidized.

    eg. 3:

    oxidation7.png

    In 3, the sum of oxidation numbers of atoms that participate in the reaction increases from -2 to +2; 3 is oxidized.

    eg. 4:

    oxidation8.png

    In 4, the sum of oxidation numbers of atoms that participate in the reaction increases from -4 to -2; 4 is oxidized.

    In most oxidations, the species oxidized either gains oxygen (eg. 2 and 3), loses hydrogen (eg. 1), or both. Traditionally, in casual usage, an oxidation reaction involving neither (eg. 4) is not referred to as an oxidation. (For example, in many undergraduate textbooks, eg. 2 and 3 are discussed under oxidation of alkenes, but eg. 4 is not.)

    see also reduction


    This page titled Oxidation 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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