H3NO3S

H3NO3S, commonly known as sulfamic acid, is an inorganic compound with the formula H3NSO3. The molecule consists of an amino group bound to a sulfonic acid group, and is often represented as H2N–SO3H. In solid form, sulfamic acid is a white, crystalline, hygroscopic substance that is highly soluble in water. It is stable under ordinary conditions but can decompose when heated, releasing gases containing sulfur and nitrogen.

Sulfamic acid is widely used as a descaling and cleaning agent due to its ability to dissolve mineral deposits such as calcium carbonate without the vigorous fumes associated with some mineral acids. It also serves as a reagent in organic synthesis, particularly for the preparation of sulfamate esters, which function as intermediates or protecting groups in various transformations. In industry, sulfamic acid can form sulfamate salts with metals and other cations, expanding its utility in catalysis and material processing.

Safety and handling are important considerations. Sulfamic acid is corrosive to skin and eyes and should be handled with appropriate protective equipment. It is non-volatile and should be stored in a cool, dry place, away from incompatible materials such as strong oxidizers. Proper ventilation is recommended when using the material in bulk quantities.

See also: sulfamate, descaling agents, sulfamic acid salts.