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Chemistry LibreTexts

Plane of Symmetry

  • Page ID
    40875
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    A plane of symmetry is an imaginary plane that bisects a molecule into halves that are mirror images of each other.

    eg. 1:

    planeofsymmetry1.png

    In 1, the vertical plane that bisects the methyl group, the carbon atom, and the hydrogen atom bisects the molecule into halves that are mirror images of each other. Therefore, it is a plane of symmetry.

    eg. 2:

    planeofsymmetry2.png

    In 2, the horizontal plane that bisects all six atoms in the molecule bisects the molecule into halves that are mirror images of each other. Therefore, it is a plane of symmetry.

    eg. 3:

    planeofsymmetry3.png

    In 3, the vertical plane that passes through the red broken line perpendicular to the plane of the cyclopropane ring bisects the molecule into halves that are mirror images of each other. Therefore, it is a plane of symmetry.


    This page titled Plane of Symmetry 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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