Barium permanganate

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Barium permanganate
Identifiers
CAS number 7787-36-2 YesY
PubChem 24587
EC number 232-110-1
Jmol-3D images Image 1
Properties
Molecular formula BaMn2O8
Molar mass 375.198 g/mol
Appearance dark violet to brown crystals
Odor odorless
Density 3.77 g/cm3
Melting point 200 °C (392 °F; 473 K) (decomposes)
Solubility in water 62.5 g/100 mL (29 °C)
Solubility decompoeses in alcohol
Structure
Crystal structure rhombic
Hazards
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Related compounds
Other cations Magnesium permanganate
Strontium permanganate
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Barium permanganate is a chemical compound, with the formula BaMn2O8. [1]

Preparation[edit]

Barium permanganate may be produced by disproportionation of barium manganate in a mildly acidic solution,[2] or by oxidation of barium manganate with strong oxidants. Preparations relying on aqueous reactions of barium manganate are extremely slow process due to the low solubility of the manganate.[2]

Reactions[edit]

Permanganic acid can be prepared by the reaction of dilute sulfuric acid with a solution barium permanganate, the insoluble barium sulfate byproduct being removed by filtering:[2]

BaMn2O8 + H2SO4 → 2 HMnO4 + BaSO4

The sulfuric acid used must be dilute; reactions of permanganates with concentrated sulfuric acid yield the anhydride, manganese heptoxide.

References[edit]

  1. ^ PubChem
  2. ^ a b c Olsen, J. C. (1900). Permanganic Acid by Electrolysys. Easton, PA: The Chemical Publishing Company.