Potassium nitrate Potassium nitrate Potassium nitrate is a chemical compound with the chemical formula KNO. It is an ionic salt of potassium ions K and nitrate ions NO, and is therefore an alkali metal nitrate. It occurs in nature as a mineral, niter. It is a source of nitrogen, from which it derives its name. 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 (black powder) and has been used since the
Group 3 element be reduced to their elements, meaning that the discovery of a new earth was equivalent to the discovery of the element within, which in this case would have been "yttrium". Until the early 1920s, the chemical symbol "Yt" was used for the element, after which "Y" came into common use. Yttrium metal was first isolated in 1828 when Friedrich Wöhler heated anhydrous yttrium(III) chloride with potassium to form metallic yttrium and potassium chloride. In 1869, Russian chemist Dmitri Mendeleev published his periodic table, which had empty spaces for elements directly above and under yttrium. Mendeleev made several predictions on the