 Okay, so let's go ahead and continue our discussion of structural isomers, doing these structural isomers, C4H10, okay? So the most obvious one, of course, would be the C's all in a line, right? In fact, if we do it this way, it's called U-ting. If we got two hydrogen's together, that's hydrogen gas bubbles away, okay? So that is a different model. The only requirement of our molecule is that it's got four carbons and ten hydrogen's. We can build this in several different ones, okay? So let's try to build it in a different one, before we go to sleep. Okay, so we could do three carbons in a row, if we wanted to, right? And put one carbon on top, just like that, okay? So that's got a different quote-unquote backbone than the other ones, okay? Online structures of both of these molecules while we're at it, okay? So remember, like Charlie Brown, well, here, let's turn it over. Up, down, so one, two, three, four, right? One, two, three, four, like that. Everybody okay with that one? So, start at the top, one, two, three, like that, and then the fourth one's down like that, okay? Why do we put it like that? Because we want it to be at the point, okay? It kind of looks weird if we do it like this, because that's not an ideal bonding, okay? So if it helps you, and erase that, we can draw it differently. We can draw it with this guy on top. So you kind of want to represent these with more idealized bonding. So in fact, those are the only structural isomers of C4H10, I guess. They have some other ones, but those aren't C4H10. Those are C4H10s. We can do some C4H10s. Let's do those. Can we erase these ones and do some C4H10s? Well, why don't we just kill this video and do its own video? Are there any questions about this?