|
| Sulfur dioxide | |
|---|---|
 | |
 | |
| 160px | |
| IUPAC name | Sulfur dioxide |
| Other names | Sulfurous anhydride Sulfur(IV) oxide |
| Identifiers | |
| CAS number | |
| PubChem | |
| EC number | 231-195-2 |
| KEGG | D05961 |
| MeSH | |
| ChEBI | CHEBI:18422 |
| RTECS number | WS4550000 |
| SMILES | O=S=O |
| Beilstein Reference | 3535237 |
| Gmelin Reference | 1443 |
| Properties | |
| Molecular formula | SO2 |
| Molar mass | 64.066 g mol−1 |
| Appearance | Colorless gas |
| Odor | Pungent; similar to a just-struck match |
| Density | 2.6288 kg m−3 |
| Melting point | -72 °C, 201 K, -98 °F |
| Boiling point | |
| Solubility in water | 94 g/L forms sulfurous acid |
| Vapor pressure | 237.2 kPa |
| Acidity (pKa) | 1.81 |
| Basicity (pKb) | 12.19 |
| −18.2·10−6 cm3/mol | |
| Viscosity | 0.403 cP (at 0 °C) |
| Structure | |
| C2 | |
| Coordination geometry | Digonal |
| Molecular shape | Dihedral |
| Dipole moment | 1.62 D |
| Thermochemistry | |
| Std enthalpy of formation ΔfH | −296.81 kJ mol−1 |
| Standard molar entropy S | 248.223 J K−1 mol−1 |
| Hazards | |
| NFPA 704 |
0 3 0 |
| U.S. Permissible exposure limit (PEL) | TWA 5 ppm (13 mg/m3) |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) | |
Sulfur dioxide (also sulphur dioxide) is the chemical compound with the formula SO2. It is a gas. It smells like burnt matches or rotten eggs. It can also cause suffocation. Sulfur dioxide is produced by volcanoes and in various industrial processes. It is also used to protect wine from oxygen and bacteria. It can be produced by burning sulfur. It dissolves in water to produce sulfurous acid. It can be oxidized to trioxide, which is dissolved in sulfuric acid to make more sulfuric acid. It is used to make sulfites. view more...
 |
|
