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Hammond’s Postulate

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    40432
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    Hammond’s postulate states that the transition state of a reaction resembles either the reactants or the products, to whichever it is closer in energy.

    In an exothermic reaction, the transition state is closer to the reactants than to the products in energy (Fig. 1). Therefore, according to Hammond’s postulate, in an exothermic reaction, the transition state resembles the reactants.

    hammondspostulate1.png

    In an endothermic reaction, the transition state is closer to the products than to the reactants in energy (Fig. 2). Therefore, according to Hammond’s postulate, in an endothermic reaction, the transition state resembles the products.

    hammondspostulate2.png


    This page titled Hammond’s Postulate 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.

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