What is Phosphoric acid?
[[File:Phosphoric acid.svg|thumb|Phosphoric acid structure]] '''Phosphoric acid''', also known as '''orthophosphoric acid''', is a [[chemical compound]]. It is also an [[acid]]. Its chemical formula is H<sub>3</sub>PO<sub>4</sub>. It contains [[hydrogen]] and [[phosphate]] [[ion]]s. Its official [[IUPAC]] name is '''trihydroxidooxidophosphorus'''. ==Properties== Phosphoric acid is a white solid. It melts easily to make a [[viscosity|viscous]] liquid. It tastes sour when diluted (mixed with a lot of water). It can be [[deprotonation|deprotonated]] three times. It is very strong, although not as much as the other acids like [[hydrochloric acid]]. It does not have any odor. It is [[corrosive]] when concentrated. Salts of phosphoric acid are called [[phosphate]]s. ==Preparation== Phosphoric acid can be made by dissolving [[phosphorus(V) oxide]] in water. This makes a very pure phosphoric acid that is good for food. A less pure form is made by reacting [[sulfuric acid]] with [[phosphate]] rock. This can be purified to make food-grade phosphoric acid if needed. ==Uses== It is used to make [[Soft drink|soda]]s sour. It is also used when a nonreactive acid is needed. It can be used to make [[hydrogen halide]]s, such as [[hydrogen chloride]]. Phosphoric acid is heated with a sodium [[halide]] to make the hydrogen halide and [[sodium phosphate]]. It is used to react with [[rust]] to make black iron(III) phosphate, which can be scraped off, leaving pure iron. It can be used to clean teeth. There are many minor uses of phosphoric acid. Phosphoric acid with a certain [[isotope]] of [[phosphorus]] is used for [[nuclear magnetic resonance]]. It is also used as an [[electrolyte]] in some [[fuel cell]]s. It can be used as a [[flux]]. It can [[etch]] certain things in [[semiconductor]] making. ==Safety== Phosphoric acid is one of the least toxic acids. When it is diluted, it just has a sour taste. When it is concentrated, it can corrode metals. ==Related pages== *[[Phosphorous acid]] *[[Hypophosphorous acid]] *[[Phosphorus