Chromium(III) sulfide

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Chromium(III) Sulfide
Cr2S3 structure.jpg
Identifiers
ECHA InfoCard 100.031.477
EC Number 234-638-8
Properties
Cr2S3
Molar mass 200.19 g/mol
Appearance Brown to black powder
Odor odorless
Density 3.77 g/cm3
Melting point 1350 °C
insoluble
+2390.0·10−6 cm3/mol
Hazards
Safety data sheet [1]
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine 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
US health exposure limits (NIOSH):
PEL (Permissible)
TWA 1 mg/m3[1]
REL (Recommended)
TWA 0.5 mg/m3[1]
IDLH (Immediate danger)
250 mg/m3[1]
Related compounds
Other anions
Chromium(III) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Chromium(III) Sulfide is the inorganic compound with the formula Cr2S3. It is a brown-black solid. Chromium sulfides are usually nonstoichiometric compounds, with formulas ranging from CrS to Cr0.67S (corresponding to Cr2S3).

Preparation[edit]

Chromium(III) sulfide can be preparared through the reaction of a stoichiometric mixture of the elements at 1000 °C[2]

It is a solid that is insoluble in water. According to X-ray crystallography, its is a combination of that of nickel arsenide (1:1 stoichiometry) and Cd(OH)2 (1:2 stoichiometry). Some metal-metal bonding is indicated by the short Cr-Cr distance of 2.78 Å.[3]

References[edit]

  1. ^ a b c "NIOSH Pocket Guide to Chemical Hazards #0141". National Institute for Occupational Safety and Health (NIOSH). 
  2. ^ Georg Brauer: Handbuch der präparativen anorganischen Chemie. 3., umgearb. Auflage. Band III. Enke, Stuttgart 1981, ISBN 3-432-87823-0, S. 1493.
  3. ^ Jellinek, F. "The structures of the Chromium Sulphides" Acta Crystallographica 1957, volume 10, p620-p628. doi:10.1107/S0365110X57002200.