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9.6B: Self-Ionization of Ammonia

  • Page ID
    33836
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    Self-ionization of ammonia is much "weaker" than water.

    \[\ce{2NH3 <=> NH4+ + NH2-}\]

    with \(K \approx 10^{-30}\) @ 223K. Since ammonia is better proton acceptor than water, the ionization of acids is relatively enhanced in liquid ammonia. For example, acetic acid is a strong acid in liquid ammonia. Liquid ammonia will therefore tolerate very strong bases such as \(\ce{C5H5-}\) that would otherwise be hydrolyzed in water.

    Ammonia is kinetically stabilized to reduction (but easily oxidized) by many reagents, e.g., the reaction

    \[\ce{ Na + NH3 -> NaNH2 + H2(g}}\]

    and is very favorable but slow in the absence of a catalyst such as Fe3+.


    9.6B: Self-Ionization of Ammonia is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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