Formula (NH4)HSO4 Boiling point 490 °C Appearance White solid | Molar mass 115.11 g/mol Density 1.78 g/cm³ | |
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Preparation properties of ammonium bisulfate or ammonium hydrogen sulfate
Ammonium bisulfate, also known as ammonium hydrogen sulfate, is a white, crystalline solid with the formula (NH4)HSO4. It is the product of the half-neutralization of sulfuric acid by ammonia.
Contents
Production
It is commonly collected as a byproduct of the "acetone cyanohydrin route" to the commodity chemical methyl methacrylate.
It can also be obtained by hydrolysis of sulfamic acid in aqueous solution, which produces the salt in high purity:
H3NSO3 + H2O → [NH4]+[HSO4]−It also arises by the thermal decomposition of ammonium sulfate:
(NH4)2SO4 → (NH4)HSO4 + NH3Applications
It can be further neutralized with ammonia to form ammonium sulfate, a valuable fertilizer. It can be used as a weaker alternative to sulfuric acid, although sodium bisulfate is much more common.
References
Ammonium bisulfate Wikipedia(Text) CC BY-SA