Description
Ferric ammonium sulfate, also known as ferric alum, is a chemical compound with the formula FeNH4(SO4)2·12H2O. It is a double salt consisting of iron(III) ions, ammonium ions, and sulfate ions, along with twelve molecules of water of crystallization. Ferric ammonium sulfate occurs as colorless to pale violet crystals with a slight ammoniacal odor. It is commonly used as a mordant in dyeing and printing textiles, as a coagulant in water treatment processes, and as a reagent in analytical chemistry, particularly in the determination of phosphate ions. Ferric ammonium sulfate also finds applications in various other industries, including paper manufacturing and pharmaceuticals.