Sulfur dioxide
|
| |||
| Names | |||
|---|---|---|---|
| IUPAC name
Sulfur dioxide
| |||
Other names
| |||
| Identifiers | |||
3D model (JSmol)
|
|||
Beilstein Reference
|
3535237 | ||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.028.359 | ||
| EC Number |
| ||
| E number | E220 (preservatives) | ||
Gmelin Reference
|
1443 | ||
| KEGG | |||
| MeSH | Sulfur+dioxide | ||
PubChem CID
|
|||
| RTECS number |
| ||
| UNII | |||
| UN number | 1079, 2037 | ||
CompTox Dashboard (EPA)
|
|||
| |||
SMILES
| |||
| Properties | |||
| SO 2 | |||
| Molar mass | 64.066 g/mol | ||
| Appearance | Colorless gas | ||
| Odor | Pungent; similar to a just-struck match[1] | ||
| Density | 2.619 kg m−3[2] | ||
| Melting point | −72 °C; −98 °F; 201 K | ||
| Boiling point | −10 °C (14 °F; 263 K) | ||
| 94 g/L[3] forms sulfurous acid | |||
| Vapor pressure | 230 kPa at 10 °C; 330 kPa at 20 °C; 462 kPa at 30 °C; 630 kPa at 40 °C[4] | ||
| Acidity (pKa) | ~1.81 | ||
| Basicity (pKb) | ~12.19 | ||
Magnetic susceptibility (χ)
|
−18.2·10−6 cm3/mol | ||
| Viscosity | 12.82 μPa·s[5] | ||
| Structure | |||
| C2v | |||
Coordination geometry
|
Digonal | ||
Molecular shape
|
Dihedral | ||
Dipole moment
|
1.62 D | ||
| Thermochemistry | |||
Std molar
entropy (S⦵298) |
248.223 J K−1 mol−1 | ||
Std enthalpy of
formation (ΔfH⦵298) |
−296.81 kJ mol−1 | ||
| Hazards | |||
| GHS labelling: | |||
Pictograms
|
|||
| Danger | |||
Hazard statements
|
H314, H331, H370[6] | ||
| NFPA 704 (fire diamond) | |||
| Lethal dose or concentration (LD, LC): | |||
LC50 (median concentration)
|
3000 ppm (mouse, 30 min) 2520 ppm (rat, 1 hr)[8] | ||
LCLo (lowest published)
|
993 ppm (rat, 20 min) 611 ppm (rat, 5 hr) 764 ppm (mouse, 20 min) 1000 ppm (human, 10 min) 3000 ppm (human, 5 min)[8] | ||
| NIOSH (US health exposure limits): | |||
PEL (Permissible)
|
TWA 5 ppm (13 mg/m3)[7] | ||
REL (Recommended)
|
TWA 2 ppm (5 mg/m3) ST 5 ppm (13 mg/m3)[7] | ||
IDLH (Immediate danger)
|
100 ppm[7] | ||
| Related compounds | |||
| Sulfur monoxide Sulfur trioxide Disulfur monoxide | |||
Related compounds
|
Ozone Selenium dioxide Tellurium dioxide Polonium dioxide | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
| |||
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula SO
2. It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced as a by-product of metals refining and the burning of sulfur-bearing fossil fuels.[9]
Sulfur dioxide is somewhat toxic to humans, although only when inhaled in relatively large quantities for a period of several minutes or more. It was known to medieval alchemists as "volatile spirit of sulfur".[10]
- ^ Sulfur dioxide Archived December 30, 2019, at the Wayback Machine, U.S. National Library of Medicine
- ^ National Center for Biotechnology Information (2025). "PubChem Compound Summary for CID 1119, Sulfur Dioxide". Archived from the original on September 24, 2023. Retrieved January 15, 2025 – via U.S. National Library of Medicine.
- ^ Lide DR, ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0487-3.
- ^ National Center for Biotechnology Information (December 18, 2018). "Hazardous Substances Data Bank: Sulfur Dioxide". PubChem. Retrieved January 15, 2025.
- ^ Miller J Jr, Shah P, Yaws C (1976). "Correlation constants for chemical compounds". Chemical Engineering. 83 (25): 153–180. ISSN 0009-2460.
- ^ "Summary of Classification and Labelling: Sulphur Dioxide". C&L Inventory. Retrieved January 15, 2025.
- ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0575". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b "Sulfur dioxide". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ Cite error: The named reference
Greenwoodwas invoked but never defined (see the help page). - ^ Wothers P (2019). Antimony, Gold, and Jupiter's Wolf: How the Elements Were Named. Oxford University Press. ISBN 978-0-19-965272-3.