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Chemistry LibreTexts

Reduction

  • Page ID
    42312
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    1. If, in a reaction, the oxidation number of an atom in a reactant decreases, the atom is said to undergo reduction.

    eg. 1:

    reduction1.png

    eg. 2:

    reduction2.png

    eg. 3:

    reduction3.png

    eg. 4:

    reduction4.png

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

    eg. 1:

    reduction5.png

    In 1, the sum of oxidation numbers of atoms that participate in the reaction decreases from 0 to -2; 1 is reduced.

    eg. 2:

    reduction6.png

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

    eg. 3:

    reduction7.png

    In 3, the sum of oxidation numbers of atoms that participate in the reaction decreases from -2 to -4; 3 is reduced.

    eg. 4:

    reduction8.png

    In 4, the sum of oxidation numbers of atoms that participate in the reaction decreases from -4 to -6; 4 is reduced.

    In most reductions, the species reduced either gains hydrogen (eg. 1 and 3), loses oxygen (eg. 2), or both. Traditionally, in casual usage, a reduction reaction involving neither is not referred to as a reduction.

    see also oxidation


    This page titled Reduction 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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