CHEMISTRY COMMUNITY

If we are trying to determine hybridization of an atom and we are given a structure but an atom in that structure does not have a full octet, do we assume that their is/are lone pairs?

Yes. For instance, oxygen is often displayed without its lone pairs, so we must account for them when determining hybridization.

Yes because we consider a lone pair as one region of electron density, which you need to determine the hybridization.

Yes--just because lone pairs are not written in a diagram does not always mean they are not there. As such, they must be accounted for in determining hybridization.