Ammonium bisulfate, also known as ammonium hydrogen sulfate, is a white,

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macr ...

line solid with the formula (NH₄)HSO₄. This salt is the product of the half-neutralization of sulfuric acid by

ammonia Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogeno ...

Production

It is commonly collected as a byproduct of the "acetone cyanohydrin route" to the commodity chemical

methyl methacrylate Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA) ...

. It can also be obtained by hydrolysis of

sulfamic acid Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, sulphamic acid and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfami ...

in aqueous solution, which produces the salt in high purity: : H₃NSO₃ + H₂O → H₄sup>+ SO₄sup>− It also arises by the thermal decomposition of

ammonium sulfate Ammonium sulfate (American English and international scientific usage; ammonium sulphate in British English); (NH4)2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitroge ...

: : (NH₄)₂SO₄ → (NH₄)HSO₄ + NH₃

Applications

It can be further neutralized with ammonia to form ammonium sulfate, a valuable

fertilizer A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from ...

. It can be used as a weaker alternative to sulfuric acid, although sodium bisulfate is much more common.

Natural occurrence

A related compound of the (NH₄)₃H(SO₄)₂ formula, occurs as the rare mineral letovicite, known from coal fire environments.

References

{{inorganic-compound-stub Ammonium compounds Sulfates