Sodium permanganate

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Sodium permanganate
Sodium permanganate.png
Potassium-perchlorate-unit-cell-3D-balls-perspective.png
Sodium permanganate solution.JPG
Identifiers
CAS number (monohydrate) 10101-50-5 (monohydrate) N
PubChem 23673458
ChemSpider 23303 YesY
RTECS number SD6650000
Jmol-3D images Image 1
Properties
Molecular formula NaMnO4
Molar mass 141.9254 g/mol
159.94 g/mol (monohydrate)
Appearance Red solid
Density 1.972 g/cm3 (monohydrate)
Melting point 36 °C, 170 °C for trihydrate
Solubility in water 90 g/100 mL
Hazards
Main hazards Oxidizer
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

Sodium permanganate is the inorganic compound with the formula NaMnO4. It is closely related to the more commonly encountered potassium permanganate, 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[edit]

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.[1]

Sodium permanganate behaves similarly to potassium permanganate. 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. Because of its hygroscopic nature, it is less useful in analytical chemistry 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[edit]

Because of its high solubility, its aqueous solutions are used as etchants in printed circuitry.[1] It is gaining popularity in water treatment for taste, odor, and zebra mussel control.[2]

References[edit]

  1. ^ a b Arno H. Reidies "Manganese Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a16_123
  2. ^ http://www.simultaneouscompliancetool.org/SCToolSmall/jsp/modules/welcome/documents/TECH23.pdf