The pure product is a colorless transparent orthorhombic crystal, and the aqueous solution is acidic. Insoluble in alcohol, acetone and ammonia. It is hygroscopic, and it is consolidated into a lump after moisture absorption. It is completely decomposed into ammonia gas, nitrogen gas, sulfur dioxide and water when heated to above 513 °C. Ammonia is released when it reacts with alkalis. It reacts with a ruthenium chloride solution to form a barium sulfate precipitate. It is also possible to cause salting out of the protein.
