 Okay, so hopefully this is what you drew. If you got it wrong, go back to the material from Unit 1 on Lewis structures and do a bit of revision because it's almost impossible to draw VSEPR structures without first being able to draw accurate Lewis structures. So the question now is, how can the bonds position themselves so that they minimise repulsion? Note that for the purposes of VSEPR, we count each collection of bonding electrons as essentially a single bond. And by this I mean, although there's a double bond joining the carbon to each oxygen, we're not trying to separate out the two bonds within each double bond. Those four electrons are strongly localised in between the carbon and oxygen atoms. What we want to know is, where can the two oxygen atoms sit so that the two double bonds are as far apart as possible? For two bonds like this, the ants is fairly easy to visualise. They have to point in opposite directions. If you were to move either oxygen out of line, it would bring the carbon-oxygen bonds closer together. So for CO2, the VSEPR drawing looks just like the Lewis structure, and we can indicate that the bond angle, that's the angle made by these two bonds, is 180 degrees. This molecular shape is very sensibly called linear.