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pKa

  • Page ID
    40874
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    Many organic species are very weakly acidic in water. Hence, their acid dissociation constants are small and tedious to work with. The quantity pKa is an attempt to solve this problem.

    pKa of a species is defined as follows:

    pKa = –logKa

    By definition, the larger the Ka of a species, the smaller its pKa.

    eg:

    pka.png

    As is evident from the above numbers, it is more convenient to work with pKa values than with Ka values when Ka values are very small.


    This page titled pKa 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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