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Characteristic Reactions of Ammonium Ion (NH₄⁺)

  • Page ID
    97260
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    General Description and Properties

    Ammonium ion is formed by the reaction between acids and aqueous ammonia:

    \[\ce{NH3(aq)+ H+(aq) <=> NH>4+(aq)} \nonumber \]

    The ammonium ion behaves chemically like the ions of the alkali metals, particularly potassium ion, which is almost the same size. All ammonium salts are white and soluble.

    Characteristic reactions of NH₄⁺

    Sodium Hydroxide

    Addition of concentrated hydroxide ion solutions evolves NH3 gas:

    \[\ce{NH4^{+}(aq) + OH^{-}(aq) <=> NH3(aq) + H2O(l)} \nonumber \]

    Nh44.gif

    The ammonia gas turns moistened red litmus paper blue. It can also be detected by its characteristic odor. This reaction serves as a confirmatory test for NH4+.

    No Reaction

    \(\ce{Cl^{-}}\), \(\ce{SO4^{2-}}\), \(\ce{NH3(aq)}\)


    This page titled Characteristic Reactions of Ammonium Ion (NH₄⁺) is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by James P. Birk.