Hydrogen sulfide
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| Names | |||
|---|---|---|---|
| Systematic IUPAC name
Hydrogen sulfide[1] | |||
Other names
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| Identifiers | |||
CAS Number
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3D model (JSmol)
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Beilstein Reference
|
3535004 | ||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.029.070 | ||
| EC Number |
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Gmelin Reference
|
303 | ||
| KEGG | |||
| MeSH | Hydrogen+sulfide | ||
PubChem CID
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| RTECS number |
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| UNII | |||
| UN number | 1053 | ||
CompTox Dashboard (EPA)
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InChI
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SMILES
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| Properties | |||
Chemical formula
|
H2S | ||
| Molar mass | 34.08 g·mol−1 | ||
| Appearance | Colorless gas | ||
| Odor | Foul, pungent, like that of rotten eggs | ||
| Density | 1.539 g.L−1 (0°C)[2] | ||
| Melting point | −85.5[3] °C (−121.9 °F; 187.7 K) | ||
| Boiling point | −59.55[3] °C (−75.19 °F; 213.60 K) | ||
Solubility in water
|
3.980 g dm−3 (at 20 °C) [4] | ||
| Vapor pressure | 1740 kPa (at 21 °C) | ||
| Acidity (pKa) | 7.0[5][6] | ||
| Conjugate acid | Sulfonium | ||
| Conjugate base | Bisulfide | ||
Magnetic susceptibility (χ)
|
−25.5·10−6 cm3/mol | ||
Refractive index (nD)
|
1.000644 (0 °C)[2] | ||
| Structure | |||
Point group
|
C2v | ||
Molecular shape
|
Bent | ||
Dipole moment
|
0.97 D | ||
| Thermochemistry | |||
Heat capacity (C)
|
1.003 J K−1 g−1 | ||
Std molar
entropy (S⦵298) |
206 J mol−1 K−1[7] | ||
Std enthalpy of
formation (ΔfH⦵298) |
−21 kJ mol−1[7] | ||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards
|
Flammable and highly toxic | ||
| GHS labelling: | |||
Pictograms
|
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Signal word
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Danger | ||
Hazard statements
|
H220, H330, H400 | ||
Precautionary statements
|
P210, P260, P271, P273, P284, P304+P340, P310, P320, P377, P381, P391, P403, P403+P233, P405, P501 | ||
| NFPA 704 (fire diamond) | |||
| Flash point | −82.4 °C (−116.3 °F; 190.8 K)[10] | ||
Autoignition
temperature |
232 °C (450 °F; 505 K) | ||
| Explosive limits | 4.3–46% | ||
| Lethal dose or concentration (LD, LC): | |||
LC50 (median concentration)
|
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LCLo (lowest published)
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| NIOSH (US health exposure limits): | |||
PEL (Permissible)
|
C 20 ppm; 50 ppm [10-minute maximum peak][8] | ||
REL (Recommended)
|
C 10 ppm (15 mg/m3) [10-minute][8] | ||
IDLH (Immediate danger)
|
100 ppm[8] | ||
| Related compounds | |||
Related hydrogen chalcogenides
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Related compounds
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Phosphine | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
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Hydrogen sulfide is a chemical compound with the formula H2S. It is a colorless chalcogen-hydride gas, and is toxic, corrosive, and flammable. Trace amounts in ambient atmosphere have a characteristic foul odor of rotten eggs.[11] Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777.[12]
Hydrogen sulfide is toxic to humans and most other animals by inhibiting cellular respiration in a manner similar to hydrogen cyanide. When it is inhaled or its salts are ingested in high amounts, damage to organs occurs rapidly with symptoms ranging from breathing difficulties to convulsions and death.[13][14] Despite this, the human body produces small amounts of this sulfide and its mineral salts, and uses it as a signalling molecule.[15]
Hydrogen sulfide is often produced from the microbial breakdown of organic matter in the absence of oxygen, such as in swamps and sewers; this process is commonly known as anaerobic digestion, which is done by sulfate-reducing microorganisms. It also occurs in volcanic gases, natural gas deposits, and sometimes in well-drawn water.
- ^ "Hydrogen Sulfide - PubChem Public Chemical Database". The PubChem Project. USA: National Center for Biotechnology Information.
- ^ a b Patnaik, Pradyot (2002). Handbook of Inorganic Chemicals. McGraw-Hill. ISBN 978-0-07-049439-8.
- ^ a b William M. Haynes (2016). CRC Handbook of Chemistry and Physics (97th ed.). Boca Raton: CRC Press. pp. 4–87. ISBN 978-1-4987-5429-3.
- ^ "Hydrogen sulfide". pubchem.ncbi.nlm.nih.gov.
- ^ Perrin, D.D. (1982). Ionisation Constants of Inorganic Acids and Bases in Aqueous Solution (2nd ed.). Oxford: Pergamon Press.
- ^ Bruckenstein, S.; Kolthoff, I.M., in Kolthoff, I.M.; Elving, P.J. Treatise on Analytical Chemistry, Vol. 1, pt. 1; Wiley, NY, 1959, pp. 432–433.
- ^ a b Zumdahl, Steven S. (2009). Chemical Principles (6th ed.). Houghton Mifflin Company. p. A23. ISBN 978-0-618-94690-7.
- ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0337". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b "Hydrogen sulfide". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ "Hydrogen sulfide". npi.gov.au.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8.
- ^ Smith, Roger P. (2010). "A Short History of Hydrogen Sulfide". American Scientist. 98 (1): 6. doi:10.1511/2010.82.6.
- ^ Shackelford, R. E.; Li, Y.; Ghali, G. E.; Kevil, C. G. (2021). "Bad Smells and Broken DNA: A Tale of Sulfur-Nucleic Acid Cooperation". Antioxidants. 10 (11): 1820. doi:10.3390/antiox10111820. PMC 8614844. PMID 34829691.
- ^ Reiffenstein, R. J.; Hulbert, W. C.; Roth, S. H. (1992). "Toxicology of Hydrogen Sulfide". Annual Review of Pharmacology and Toxicology. 32: 109–134. doi:10.1146/annurev.pa.32.040192.000545. PMID 1605565.
- ^ Bos, E. M; Van Goor, H; Joles, J. A; Whiteman, M; Leuvenink, H. G (2015). "Hydrogen sulfide: Physiological properties and therapeutic potential in ischaemia". British Journal of Pharmacology. 172 (6): 1479–1493. doi:10.1111/bph.12869. PMC 4369258. PMID 25091411.