Ammonium iodide is the inorganic compound with the formula NH4I. It is an ionic compound. It takes the form of a white solid, though impure samples appear yellow. This salt consists of ammonium cation and an iodide anion.Holleman, A. F.; Wiberg, E. Inorganic Chemistry Academic Press: San Diego, 2001. . It can be prepared by the action of hydroiodic acid on ammonia. It is easily soluble in water, from which it crystallizes in cubes. It is also soluble in ethanol.
Structure Ammonium iodide is a salt that crystallizes in a motif akin those for the alkali metal iodides and most other ammonium halides. Several phases have been characterized, which are similar but not identical to those of ammonium chloride.
Under pressure, the compound melts congruently. Preparation Ammonium iodide can be made in lab by treating ammonia with iodine and the reductant hydrogen peroxide:
Uses Ammonium iodide is used as a dietary supplement to treat iodine deficiency.
Properties and reactions Vinyl sulfones have been prepared using ammonium iodide.
In green chemistry, ammonium iodide and an oxidant (e.g., H2O2) iodinate ketones and aromatic compounds.
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