Chromium(II) sulfide explained

Chromium(II) sulfide is an inorganic compound of chromium and sulfur with the chemical formula CrS.^{[1] [2] [3]} The compound forms black hexagonal crystals, insoluble in water.^[4]

Synthesis

Chromium(II) sulfide may be formed by reaction of chromium metal with sulfur or hydrogen sulfide at high temperature. It may also be formed by reacting chromium(III) chloride with H₂S, reducing chromium(III) sulfide with hydrogen, or by double replacement reaction of lithium sulfide with chromium(II) chloride.^[5]

Cr + S -> CrS

Cr + H2S -> CrS + H2

2CrCl3 + 3H2S -> 2CrS + S + 6HCl

Cr2S3 + H2 -> 2CrS + H2S

Li2S + CrCl2 -> 2LiCl + CrS

Physical properties

Chromium(II) sulfide forms black paramagnetic crystals of two crystalline modifications:^[6]

• α-CrS, superstructured phase, hexagonal system, cell parameters a = 1.200 nm, c = 1.152 nm.
• β-CrS, monoclinic system, cell parameters a = 0.594 nm, b = 0.341 nm, c = 0.563 nm, β = 91.73°.

Chromium(II) sulfide is a semiconductor,^{[7] [8]} and is also used as a catalyst.^[9]

Chemical properties

Chromium(II) sulfide slowly oxidizes in air:

2CrS + 7O2 -> 2Cr2O3 + 4SO2

Notes and References

1. Book: Bretherick . L. . Bretherick's Handbook of Reactive Chemical Hazards . 27 October 2016 . . 978-1-4831-6250-8 . 1074 . 1 November 2021 . en.
2. Book: Wiberg . Egon . Holleman . A. F. . Wiberg . Nils . Inorganic Chemistry . 2001 . . 978-0-12-352651-9 . 1372 . 1 November 2021 . en.
3. Book: Sr . Richard J. Lewis . Hazardous Chemicals Desk Reference . 13 June 2008 . . 978-0-470-18024-2 . 670 . 1 November 2021 . en.
4. Book: Lide . David R. . 1998 Freshman Achievement Award . 26 June 2006 . . 978-0-8493-0594-8 . 6-111 . 1 November 2021 . en.
5. Wadhawan . Amar R. . Livi . Kenneth J. . Stone . Alan T. . Bouwer . Edward J. . 2015-03-17 . Influence of oxygenation on chromium redox reactions with manganese sulfide (MnS(s)) . Environmental Science & Technology . 49 . 6 . 3523–3531 . 10.1021/es5057165 . 1520-5851 . 25688449 .
6. PubChem . Chromium sulfide (CrS) . live . https://web.archive.org/web/20220904015205/https://pubchem.ncbi.nlm.nih.gov/compound/Chromium_II_-sulfide . 2022-09-04 . 2022-09-04 . . 2002 . 40 . 1 . 24–26 . . en . 11955372.
7. Book: Erwin. Riedel. Christoph. Janiak . Anorganische Chemie . Walter de Gruyter . 978-3-11-022566-2 . German. 2011 . 732 .
8. Book: A. F.. Holleman. E.. Wiberg. N.. Wiberg. Lehrbuch der Anorganischen Chemie. 101. Auflage.. German. Walter de Gruyter. 1995. 3-11-012641-9. 1451.
9. Book: Macintyre . Jane E. . Dictionary of Inorganic Compounds . 23 July 1992 . . 978-0-412-30120-9 . 3082 . 1 November 2021 . en.