Silver sulfate

Silver sulfate is the inorganic compound with the formula Ag2SO4. It is a white solid with low solubility in water.

Preparation and structure
Silver sulfate precipitates as a solid when an aqueous solution of silver nitrate is treated with sulfuric acid:
 * 2 AgNO3 + H2SO4 -> Ag2SO4 + 2 HNO3

It is purified by recrystallization from concentrated sulfuric acid, a step that expels traces of nitrate. Silver sulfate and anhydrous sodium sulfate adopt the same structure.

Silver(II) sulfate
The synthesis of silver(II) sulfate (AgSO4) with a divalent silver ion instead of a monovalent silver ion was first reported in 2010 by adding sulfuric acid to silver(II) fluoride (HF escapes). It is a black solid that decomposes exothermically at 120 °C with evolution of oxygen and the formation of the pyrosulfate.


 * AgF2 + H2SO4 -> AgSO4 + 2 HF
 * 4 AgSO4 -> 2 Ag2S2O7 + O2