Sodium manganate

{{chembox

|verifiedrevid = 436819985

|ImageFile = File:2.svg class=skin-invert File:Manganate.png

|Section1={{Chembox Identifiers

|CASNo = 15702-33-7

|PubChem = 22558567

|StdInChI=1S/Mn.2Na.4O/q;2*+1;;;2*-1

|StdInChIKey = BNBLBRISEAQIHU-UHFFFAOYSA-N

|SMILES = [O-] [Mn](=O)(=O)[O-].[Na+].[Na+]

}}

|Section2={{Chembox Properties

|Na=2 | Mn=1 | O=4

|Appearance = deep green solid

}}

|Section3={{Chembox Related

|OtherCompounds = Barium manganate

}}

}}

Sodium manganate is the inorganic compound with the formula Na₂MnO₄. This deep green solid is a rarely encountered analogue of the related salt K₂MnO₄. Sodium manganate is rare because it cannot be readily prepared from the oxidation of manganese dioxide and sodium hydroxide. Instead this oxidation reaction tends to stop at producing sodium hypomanganate, Na₃MnO₄, and even this Mn(V) salt is unstable in solution.{{cite encyclopedia|author=Arno H. Reidies |title=Manganese Compounds|encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry|year=2002|publisher=Wiley-VCH|place= Weinheim|doi=10.1002/14356007.a16_123|isbn=3-527-30673-0}} Sodium manganate can be produced by reduction of sodium permanganate under basic conditions:

:4 NaOH + 4NaMnO₄ → 4 Na₂MnO₄ + 2 H₂O + O₂

Because NaMnO₄ is difficult to prepare, sodium permanganate is more expensive than potassium permanganate.