I've been scratching my head on this one for awhile here. In a carbonyl sulfide (COS) molecule, what is the hybridization state of oxygen?
Carbonyl sulfide is composed of a single carbon atom double bonded to oxygen and sulfur atoms. The sulfur and oxygen atoms each harbor two lone pairs.
Looking at oxygen, I count electron-dense groups:
- There is one bonded atom
- There are two lone pairs
This should amount to an sp2 hybridized orbitals for oxygen, before exceptions are accounted for.
Checking if any lone pairs are delocalized:
- Oxygen both participates in a pi-bond and is adjacent to a carbon that participates in a pi-bond
This is where I'm stuck. Are any of oxygen's lone electron pairs delocalized due to these facts? Is the hybridized orbital not sp2 for oxygen?