Mercury sulfide

Mercury sulfide
Names
IUPAC name
Mercury sulfide
Other names
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.014.270
EC Number
  • 215-696-3
UNII
UN number 2025
  • InChI=1S/Hg.S
    Key: QXKXDIKCIPXUPL-UHFFFAOYSA-N
  • [S]=[Hg]
Properties
HgS
Molar mass 232.65 g·mol−1
Density
  • α-HgS: 8.17 g/cm3
  • β-HgS: 7.70 g/cm3[1]
Melting point
  • α-HgS: 344 °C (651 °F; 617 K), transforms to β-HgS
  • β-HgS: 820 °C (1,510 °F; 1,090 K)
[1]
insoluble
Solubility in ethanol soluble (β-HgS)[1]
Band gap 2.1 eV (direct, α-HgS)[2]
−55.4×10−6 cm3/mol (α-HgS)[1]
2.9003 (α-HgS)[3]
Thermochemistry[1]
48.4 J⋅mol−1·K-1
82.4 J⋅mol−1·K-1
−58.2 kJ⋅mol−1
−50.5 kJ⋅mol−1
Hazards
GHS labelling:
GHS06: ToxicGHS07: Exclamation markGHS08: Health hazardGHS09: Environmental hazard
Danger
H300, H310, H317, H330, H373, H410
P261, P272, P280, P302+P352, P321, P333+P313, P363, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
4
0
0
Safety data sheet (SDS) Fisher Scientific
Related compounds
Other anions
Other cations
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references

Mercury sulfide or mercury(II) sulfide is a chemical compound composed of the chemical elements mercury and sulfur. It is represented by the chemical formula HgS. It is virtually insoluble in water.[4]

Crystal structure

Structure of a-HgS looking at the a-axis
Structure of a-HgS looking at the c-axis

HgS is dimorphic with two crystal forms:

  • Red cinnabar (α-HgS) is the form in which mercury is most commonly found in nature. Cinnabar has a rhombohedral crystal system. Crystals of α-HgS are optically active. This is caused by helices in the structure.[5]
  • Black metacinnabar (β-HgS) is less common in nature and adopts the zinc blende crystal structure (T2d-F43m).

Preparation and chemistry

β-HgS precipitates as a black solid when Hg(II) salts are treated with H2S. The reaction is conveniently conducted with an acetic acid solution of mercury(II) acetate. With gentle heating of the slurry, the black polymorph converts to the red form.[6] β-HgS is unreactive to all but concentrated acids.[4]

Mercury is produced from the cinnabar ore by roasting in air and condensing the vapour.[4]

HgS → Hg + S

Uses

Cinnabar (red portion of specimen)

When α-HgS is used as a red pigment, it is known as cinnabar. The tendency of cinnabar to darken has been ascribed to conversion from red α-HgS to black β-HgS. However β-HgS was not detected at excavations in Pompeii, where originally red walls darkened, and was attributed to the formation of Hg-Cl compounds (e.g., corderoite, calomel, and terlinguaite) and calcium sulfate, gypsum.[7]

As the mercury cell as used in the chlor-alkali industry (Castner–Kellner process) is being phased out over concerns over mercury emissions, the metallic mercury from these setups is converted into mercury sulfide for underground storage.

It has been studied for use in photoelectrochemical cells.[8]

See also

References

  1. ^ a b c d e Haynes, William M., ed. (2016). CRC Handbook of Chemistry and Physics (97th ed.). Boca Raton, Florida: CRC Press. pp. 4–74, 4–129, 5–26. ISBN 9781498754293.
  2. ^ Berger, Lev Isaakovich (1997). Semiconductor materials. Boca Raton: CRC Press. ISBN 0-8493-8912-7.
  3. ^ "Refractive index of HgS (Mercury sulfide) - Bond-o". refractiveindex.info. Retrieved 8 April 2026.
  4. ^ a b c Greenwood, Norman N.; Earnshaw, Alan (1984). Chemistry of the Elements. Oxford: Pergamon Press. p. 1406. ISBN 978-0-08-022057-4.
  5. ^ A. M. Glazer, K. Stadnicka (1986). "On the origin of optical activity in crystal structures". J. Appl. Crystallogr. 19 (2): 108–122. Bibcode:1986JApCr..19..108G. doi:10.1107/S0021889886089823. S2CID 96545158.
  6. ^ Newell, Lyman C.; Maxson, R. N.; Filson, M. H. "Red Mercuric Sulfide". Inorganic Syntheses. Vol. 1. pp. 19–20. doi:10.1002/9780470132326.ch7. ISBN 9780470132326.
  7. ^ Cotte, M; Susini J; Metrich N; Moscato A; Gratziu C; Bertagnini A; Pagano M (2006). "Blackening of Pompeian Cinnabar Paintings: X-ray Microspectroscopy Analysis". Anal. Chem. 78 (21): 7484–7492. doi:10.1021/ac0612224. PMID 17073416.
  8. ^ Davidson, R. S.; Willsher, C. J. (March 1979). "Mercury(II) sulphide: A Photo-stable Semiconductor". Nature. 278 (5701): 238–239. Bibcode:1979Natur.278..238D. doi:10.1038/278238a0. ISSN 1476-4687. S2CID 4363745.
This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.