Potassium manganate

Template:Chembox AllOtherNamesTemplate:Chembox headerbarTemplate:Chembox IndexlistTemplate:Chembox JmolTemplate:Chembox ChEMBLTemplate:Chembox ChemSpiderIDTemplate:Chembox ECHATemplate:Chembox ECNumberTemplate:Chembox E numberTemplate:Chembox IUPHAR ligandTemplate:Chembox UNIITemplate:Chembox headerbarTemplate:Chembox SolubilityInWaterTemplate:Chembox headerbarTemplate:Chembox Footer
Potassium manganate
ChEBI
DrugBank
KEGG
PubChem {{{value}}}
SMILES {{{value}}}
K2MnO4
Molar mass 197.132 g/mol
Appearance dark green crystals
Density 2.78 g/cm3, solid
Melting point Template:Chembox CalcTemperatures
Acidity (pKa) 7.1
isomorphous with K2SO4
tetrahedral anion
Hazards
Main hazards oxidizer
NFPA 704
0
1
1
OX
R-phrases 8-36/37/38
S-phrases 17-26-36/37/39
Related compounds
Related compounds KMnO4
MnO2
K2CrO4
K2FeO4
Template:Chembox Footer/trackingScript error: No such module "TemplatePar".

Potassium manganate is a chemical compound. Its chemical formula is K2MnO4. It contains potassium and manganate ions.

Properties

Potassium manganate is a green solid. It can disproportionate into potassium permanganate and manganese(IV) oxide. This happens in acidic pH. This reaction, because of its color change, is known as a "chemical chameleon".

Preparation

It is made by reacting manganese(IV) oxide with very hot potassium hydroxide. Sometimes oxygen or potassium nitrate is used as the oxidizing agent. This makes potassium manganate. Normally the potassium manganate is converted to potassium permanganate. Potassium permanganate is more common. Potassium iodide can reduce potassium permanganate to potassium manganate. It can also be made by reacting hot potassium permanganate with potassium hydroxide. This makes oxygen and potassium manganate.

Uses

Potassium manganate does not have many uses. It is mainly made when potassium permanganate is made.

Safety

Potassium manganate is a moderate oxidizing agent. When it is reduced, it can made black or brown stains on glass, clothing, or skin.

Related pages