Chromium (III) sulfide
Crystal structure | ||||||||||||||||
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__ Cr 3+ __ S 2− | ||||||||||||||||
General | ||||||||||||||||
Surname | Chromium (III) sulfide | |||||||||||||||
other names |
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Ratio formula | Cr 2 S 3 | |||||||||||||||
Brief description |
brown odorless solid |
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properties | ||||||||||||||||
Molar mass | 200.18 g mol −1 | |||||||||||||||
Physical state |
firmly |
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density |
3.77 g cm −3 |
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Melting point |
1350 ° C |
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solubility |
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safety instructions | ||||||||||||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Chromium (III) sulfide is an inorganic chemical compound of chromium from the group of sulfides .
Extraction and presentation
Chromium (III) sulfide can be produced by reacting a stoichiometric mixture of chromium and sulfur at 1000 ° C
or from chromium (III) chloride or chromium (III) oxide with hydrogen sulfide at 650 ° C.
properties
Chromium (III) sulfide is a brown, odorless solid that is insoluble in water. It has a trigonal crystal structure with the space group P 3 1 c (space group no.163) . This corresponds to the nickel arsenide type , with 2/3 ordered voids being present in every second layer. When the compound melts, it decomposes to form chromium (II) sulfide , releasing sulfur , and other phases such as Cr 3 S 4 , Cr 5 S 6 and Cr 7 S 8 are also formed in the meantime . Chromium (III) sulfide is resistant to non-oxidizing acids , but converts to chromium (VI) compounds with oxidizing alkaline solutions . When alkali sulfides are melted with chromium (III) sulfide, thiochromates (III) are formed.
Individual evidence
- ↑ a b c d e f g h data sheet Chromium (III) sulfide, 99% (metals basis) from AlfaAesar, accessed on June 29, 2013 ( PDF )(JavaScript required) .
- ↑ 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. 1493.
- ^ A b A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 , p. 1451.
- ↑ Roger Blachnik (Ed.): Paperback for chemists and physicists . Volume III: Elements, Inorganic Compounds and Materials, Minerals . founded by Jean d'Ans, Ellen Lax. 4th, revised and revised edition. Springer, Berlin 1998, ISBN 3-540-60035-3 , pp. 406 ( limited preview in Google Book search).
- ↑ Erwin Riedel, Christoph Janiak: Inorganic Chemistry . Walter de Gruyter, 2011, ISBN 3-11-022566-2 , p. 732 ( limited preview in Google Book search).
- ^ Mary Eagleson: Concise Encyclopedia Chemistry . Walter de Gruyter, 1994, ISBN 3-11-011451-8 , p. 225 ( limited preview in Google Book Search).