Carbonyl Sulfide
Definition and meaning of Carbonyl Sulfide in chemistry.
Carbonyl sulfide is a colorless, linear triatomic gas with the formula OCS, in which a central carbon atom is double-bonded to one oxygen atom and one sulfur atom (O=C=S).
In more detail
Structurally, carbonyl sulfide is analogous to carbon dioxide with one oxygen atom replaced by sulfur, giving it a similar linear geometry but a slightly polar bond arrangement due to the asymmetry between oxygen and sulfur. It is the most abundant sulfur-containing gas in Earth's atmosphere, released by oceans, soils, volcanoes, and biomass burning, and it survives long enough in the troposphere to reach the stratosphere, where its slow oxidation contributes to the persistent Junge sulfate aerosol layer. In the presence of water or basic catalysts it hydrolyzes to hydrogen sulfide and carbon dioxide, a reaction exploited industrially to scrub it from natural gas and petroleum feedstocks.
Key facts
| Formula | OCS (also written COS) |
|---|---|
| Molar Mass | 60.07 g/mol |
| Structure | Linear, O=C=S, bond angle 180° |
| Field | Inorganic Chemistry |
Carbonyl sulfide gas is used as a fumigant to control insect pests in stored grain and dried fruit, serving as a lower-toxicity alternative to methyl bromide.
Frequently asked questions
Is carbonyl sulfide the same as carbon disulfide?
No. Carbon disulfide is CS2, with sulfur on both sides of the carbon; carbonyl sulfide (OCS) has one oxygen and one sulfur bonded to the central carbon.
Is carbonyl sulfide dangerous to breathe?
Yes, it is toxic by inhalation and can cause respiratory and neurological effects at high concentrations, so it is handled as a hazardous gas despite its natural atmospheric presence.