Product name: POTASSIUM NITRATE Chemical formula: KNO3 Molecular weight: 101,102 Physical state, form and color: White and hygroscopic crystals or prills CAS No. 7757 79 1 UN identification number: 1486 Hazard class or Division: 5.1 (Oxidizer) The chemical compound potassium nitrate is a naturally occurring mineral source of nitrogen. It is a nitrate with chemical formula KNO3. Its common names include saltpetre (from Medieval Latin sal petrae: "stone salt" or possibly "salt of Petra"), American English saltpeter, Chilean saltpetre, Nitrate of potash and nitre. The name saltpeter is also applied to sodium nitrate. One of the most useful applications of potassium nitrate is in the production of nitric acid, by adding concentrated sulfuric acid to an aqueous solution of potassium nitrate, yielding nitric acid and potassium sulfate which are separated through fractional distillation. Potassium nitrate is also used as a fertilizer, as a model rocket propellant, and in several fireworks such as smoke bombs, in which a mixture with sugar produces a smoke cloud of 600 times their own volume. In the process of food preservation, potassium nitrate is a common ingredient of salted meat.