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Lewis Theory

  • Page ID
    39037
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    According to Brønsted-Lowry theory, only a species containing at least one hydrogen atom has the potential to act as an acid in a reaction. Lewis theory is an attempt to extend the concept of acidity beyond species containing hydrogen. According to Lewis theory, in a reaction, a species that accepts a pair of electrons to form a new covalent bond is an acid, and a species that contribute s a pair of electrons toward a new covalent bond is a base.

    eg. 1:

    lewistheory1.png

    In this reaction, \(BF_3\) accepts a pair of electrons from \(F^-\) to form a new covalent bond and, therefore, acts as an acid; \(F^-\) contributes a pair of electrons toward a new covalent bond with \(BF_3\) and, therefore, acts as a base.

    In a reaction a species that acts as an acid according to Lewis theory is called a Lewis acid and a species that acts as a base a Lewis base.

    lewistheory2.png

    eg. 2:

    lewistheory3.png


    This page titled Lewis Theory 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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