Chromium(III) bromide

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Chromium(III) bromide
Kristallstruktur Bismut(III)-iodid.png
Identifiers
CAS number 10031-25-1, 13478-06-3 (hexahydrate)
PubChem 82309
ChemSpider 74280
EC number 233-088-6
Jmol-3D images Image 1
Properties
Molecular formula Br3Cr
Molar mass 291.71 g mol−1
Appearance Black lustrous crystals; green in transmitted light, reddish in reflected light[1]
Density 4.25 g/cm3[2]
Melting point 1130 °C (anhydrous)[2]
79 °C (hexahydrate)
Solubility in water insoluble in cold water, soluble with addition of Chromium(II) ion salts,[1] soluble in hot water[2]
Structure
Crystal structure trigonal
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Chromium(III) bromide is an inorganic compound with the chemical formula CrBr3. It is used in catalysts for the polymerization of olefins.

Synthesis[edit]

Desiccated bromine vapor is passed over chromium powder at 1000 °C for approximately 45–60 minutes, and is purified by extracting with absolute diethyl ether to remove any CrBr2, and is subsequently washed with absolute diethyl ether and absolute ethanol.[1]

References[edit]

  1. ^ a b c Brauer, Georg (1965) [1962]. Handbuch Der Präparativen Anorganischen Chemie [Handbook of Preparative Inorganic Chemistry] (in German) 2. Stuttgart; New York, New York: Ferdinand Enke Verlag; Academic Press, Inc. p. 1340. ISBN 978-0-32316129-9. Retrieved 2014-01-10. 
  2. ^ a b c Perry, Dale L. (2011). Handbook of Inorganic Compounds, Second Edition. Boca Raton, Florida: CRC Press. p. 122. ISBN 978-1-43981462-8. Retrieved 2014-01-10.