Mercury(II) sulfate

Mercury(II) sulfate, also known as mercuric sulfate, is a chemical compound. Its chemical formula is HgSO4. It has mercury and sulfate ions in it. The mercury is in its +2 oxidation state.
Properties.
Mercury(II) sulfate is a colorless solid. It reacts with hot water to make sulfuric acid and a mercury oxysulfate that does not dissolve. It is an oxidizing agent.
Preparation.
Mercury(II) sulfate is made by dissolving a small amount of mercury metal in concentrated sulfuric acid. It can also be made by reacting mercury(II) oxide with sulfuric acid.
Uses.
Mercury(II) sulfate is used as a catalyst in making acetaldehyde. Some byproducts of this reaction that have mercury in them are thought to have poisoned many people in Japan (Minamata disease).