Cobalt (II) bromide
Crystal structure | ||||||||||
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__ Co 2+ __ Br - | ||||||||||
General | ||||||||||
Surname | Cobalt (II) bromide | |||||||||
other names |
Cobalt dibromide |
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Ratio formula | CoBr 2 | |||||||||
Brief description |
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properties | ||||||||||
Molar mass | 218.74 g mol −1 | |||||||||
Physical state |
firmly |
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density |
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Melting point |
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solubility |
soluble in acetone, ethanol and methanol |
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safety instructions | ||||||||||
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Toxicological data | ||||||||||
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Cobalt (II) bromide is a chemical compound of cobalt and is one of the bromides .
Extraction and presentation
Cobalt (II) bromide can be obtained by reacting cobalt with bromine .
It can also be obtained by thermal decomposition of the hexahydrate at 130–150 ° C.
The preparation from cobalt (II) acetate tetrahydrate and acetyl bromide is also possible .
properties
Cobalt (II) bromide is a green, hygroscopic solid that changes to the red hexahydrate in air. It is easily soluble in water with a red color. Cobalt (II) bromide has a cadmium iodide crystal structure. The red hexahydrate dissolves in air . With concentrated sulfuric acid or when heated to 130–140 ° C, it gives off all water of crystallization. At 100 ° C, the hexahydrate gives off water of crystallization and changes into the purple-colored dihydrate. The dihydrate has a crystal structure with the space group C 2 / m (space group no. 12) and the lattice parameters a = 7.630, b = 8.770, c = 3.765 Å and β = 97.54 °.
use
Cobalt (II) bromide can be used as a catalyst in the oxidation of organic compounds.
Individual evidence
- ↑ a b c Erwin Riedel: Inorganic Chemistry. 6th edition, Walter de Gruyter, 2004, ISBN 3-11-018168-1 , p. 834.
- ↑ a b c d Georg Brauer (Ed.) U. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0 , p. 1661.
- ↑ a b c d e f g data sheet Cobalt (II) bromide, 99% from Sigma-Aldrich , accessed on June 21, 2017 ( PDF ).
- ^ A b c Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . Taylor & Francis US, 2011, ISBN 1-4398-1462-7 , pp. 483 ( limited preview in Google Book search).
- ↑ Cobalt dibromide. In: webelements.com. Retrieved June 21, 2017 (English).
- ↑ B. Morosin: Crystal Structure of Manganese (II) and Cobalt (II) Bromide Dihydrate. In: The Journal of Chemical Physics. 47, 1967, p. 417, doi: 10.1063 / 1.1711911 .
- ↑ Data sheet Cobalt (II) bromide hydrate from Sigma-Aldrich , accessed on January 30, 2012 ( PDF ).