What is Potassium nitrate?
[[File:potassium nitrate structure.png|thumb|right|]] [[File:Potassium nitrate.jpg|thumb|right|Potassium Nitrate]] '''Potassium nitrate''' is a [[chemical compound]]. It has the [[chemical formula]] KNO<sub>3</sub>. It contains [[potassium]] and [[nitrate]] [[ion]]s. It is often called '''saltpeter'''. ==Properties== Potassium nitrate is a colorless solid. It dissolves in water. It is a common source of the nitrate ion. Potassium nitrate is a strong [[oxidizing agent|oxidizer]]. It decomposes to potassium nitrite and oxygen when heated. Its [[pH]] is almost neutral. It burns with a lilac flame. ==Production== It can be made by reacting [[ammonium nitrate]] with [[potassium hydroxide]]. It can also be made by reacting [[potassium chloride]] with ammonium nitrate. It might be made by reacting potassium hydroxide or [[potassium carbonate]] with [[nitric acid]]. ==Occurrence== Saltpeter is a mineral form of potassium nitrate. It is only found in very dry areas. It is one of the few minerals that have nitrogen in them. == Uses == Potassium nitrate is used in [[explosives]]. [[Oxygen]] from the air is the most common [[chemical]] that is used for [[oxidation]], which is how most [[fire]]s and [[explosion]]s happen. Some explosions will use up oxygen so quickly, though, that there is not enough to finish the [[chemical reaction|reaction]], and the explosion is not very strong. Potassium nitrate replaces the need for oxygen and takes up much less space, which lets the explosion be stronger and faster. It is a main ingredient of [[gunpowder]]. Potassium nitrate is also used in [[rocket engine|rocket fuel]] for the same reason as in explosives, except that the goal is to let the fuel burn longer, not faster. Potassium nitrate is used as a [[fertilizer]], to help plants grow faster and grow in more places where it might be hard for them to grow otherwise. It can also be used to decay tree stumps. ==Safety== Potassium nitrate is a [[poison]] and will cause permanent injury when improperly handled. It also can start