what is potassium nitrate
Potassium nitrate is a chemical compound with the chemical formula K N O 3. It is an ionic salt of potassium ions K + and nitrate ions NO 3 â .It occurs as a mineral niter and is a natural solid source of nitrogen. Potassium nitrate is one of several nitrogen-containing compounds collectively referred to as saltpeter or saltpetre.Major uses of potassium nitrate are in fertilizers, tree stump removal, rocket propellants and fireworks.It is one of the major constituents of gunpowder (blackpowder) and has been used since the Middle Ages as a food preservative.otassium nitrate is used in fertilizers as a source of nitrogen and potassium â two of the macronutrients for plants. When used by itself, it has an NPK rating of 13-0-44.