Sodium permanganate is the

inorganic compound In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemis ...

with the formula Na MnO₄. It is closely related to the more commonly encountered

potassium permanganate Potassium permanganate is an inorganic compound with the chemical formula KMnO4. It is a purplish-black crystalline salt, that dissolves in water as K+ and , an intensely pink to purple solution. Potassium permanganate is widely used in the c ...

, but it is generally less desirable, because it is more expensive to produce. It is mainly available as the monohydrate. This salt absorbs water from the atmosphere and has a low melting point. Being about 15 times more soluble than KMnO₄, sodium permanganate finds some applications where very high concentrations of MnO₄⁻ are sought.

Preparation and properties

Sodium permanganate cannot be prepared analogously to the route to KMnO₄ because the required intermediate manganate salt, Na₂MnO₄, does not form. Thus less direct routes are used including conversion from KMnO₄.Arno H. Reidies "Manganese Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. Sodium permanganate behaves similarly to

. It dissolves readily in water to give deep purple solutions, evaporation of which gives prismatic purple-black glistening crystals of the monohydrate NaMnO₄·H₂O. The potassium salt does not form a

hydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

. Because of its

hygroscopic Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance' ...

nature, it is less useful in

analytical chemistry Analytical chemistry studies and uses instruments and methods to separate, identify, and quantify matter. In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separati ...

than its potassium counterpart. It can be prepared by the reaction of manganese dioxide with sodium hypochlorite: : 2 MnO₂ + 3 NaClO + 2 NaOH → 2 NaMnO₄ + 3 NaCl + H₂O

Applications

Because of its high solubility, its aqueous solutions are used as etchants in printed circuitry. It is gaining popularity in water treatment for taste, odor, and

zebra mussel The zebra mussel (''Dreissena polymorpha'') is a small freshwater mussel. The species originates from the lakes of southern Russia and Ukraine, but has been accidentally introduced to numerous other areas and has become an invasive species in ma ...

control. The

V-2 rocket The V-2 (german: Vergeltungswaffe 2, lit=Retaliation Weapon 2), with the technical name ''Aggregat 4'' (A-4), was the world’s first long-range guided ballistic missile. The missile, powered by a liquid-propellant rocket engine, was develop ...

used it in combination with

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3 ...

to drive a steam

turbopump A turbopump is a propellant pump with two main components: a rotodynamic pump and a driving gas turbine, usually both mounted on the same shaft, or sometimes geared together. They were initially developed in Germany in the early 1940s. The purpo ...

References

{{Manganese compounds Sodium compounds Permanganates Oxidizing agents Disinfectants