Graphene is simply carbon. Wouldn’t graphene oxide merely be CO2?
CO2 is a stand-alone molecule. Graphene is a molecular orientation which forms sheets and therefore, different sharing of electrons between molecules to form bonds that hold them all together.
Umm, no.
Carbon exists in several different forms: charcoal is nominally pure carbon but with impurities; diamond is mostly pure carbon in a face-centered cubic structure; “Buckyballs” are C-60 in a (kind of, if you squint) soccer-ball shape. Graphene is a *sheet* of carbon atoms. It can have a number of different oxygen-bearing substrates, e.g. carboxyl or hydroxyl groups, or even epoxides or carbonyl groups.
You’re thinking of what happens when you burn ordinary carbon in sufficient oxygen such that each carbon atom forms a product of carbon dioxide, a linear double-bonded molecule with carbon in the center, sigma and pi-bonding to the oxygens on either side.