 OK. So what I want you guys to do first is help me figure out what is the molecular formula of this compound. So remember what we said. Carbons are going to be bonded to or have four different bonds on them. And nitrogen's three and hydrogen's one. And also recall, of course, that at the intersection of every line, there's a carbon. And at the end of every line, there's a carbon. So let's count carbons first. So carbons, you guys can help me out if you want. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, right? OK, so there's 13 carbons. Does that make sense to everybody? OK, hydrogen's now. So remember, every one of those carbons had to have how many bonds? Four, right? So every bond that's not shown has to be a bond to a hydrogen. So how many bonds are shown from this carbon? Just one. So how many hydrogens have to be on that carbon? Three. Is everybody OK with that? So I'm going to go a little faster now for the other ones. So you guys can help me out if you can get them as fast as I can. So here, 3, right? Then 3, so that's 6, right? 1, so 7, right? 1, 8, 1, 9, 2, that's 11, right? So 0, so still 11, 1, so 12, 13, 14, 0. So still 14, 1, so 15, 16, so 19, right? Explain how. We'll draw this thing out, OK? We'll draw it out in a second, OK? So since we're recording, let's just finish up this problem. And of course, we have oxygen and nitrogen, OK? So oftentimes, you'll see the molecular formulas for the rest of the atoms in alphabetical order, OK? So nitrogen and atoms. So would that be the molecular formula? For those of you who help me with it, I think so too, OK? So for that question, let's just tackle that question and we'll do our other one. We'll record a different video for the other thing that we want to do. But let's just draw this thing out showing all the carbons and hydrogens, like the big Lewis structure, OK? So it's going to be huge over here. So I'm just going to first draw the carbon skeleton here, OK? And then we'll add our hydrogens to that, OK? So 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13. Does that make sense with the carbons? OK, so just to finish up the problem, right? So each carbon has to have how many bonds now? Four. Four, so they have to be bonded to what? Atoms, hydrogens, so let's just put them on there. So let's just go about counting the hydrogens just to make sure. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, OK? And then, of course, the N and the O. Are there any questions about this type of thing? They're all sitting at 109. So are they? That's a good question. Let's talk about that. So what's the bond angle here? 109.5 here. 109, 109, 109, 104.5, very good. 109, how many electron groups? How many electron groups? Oh, wait, it's 120. How many electron groups are there? Three. And how many of them are lone pairs? Zero, right? So it's trigonal planar, right? So it's 120. What's this one? 120, 120, 120, 120, 120, 120. 120, 109 and a half. This one here, yeah, it's a little less than 120, OK? That'd be the way to say it. If you want to think about it, all of these atoms, this one, this one, this one, this one, this one, this one, this one, this one, this one, this one, this one, this one, and this one, are all in the same plane as each other. Because they're all 120 degrees, they're all trigonal planar, right? So they all have, it's a flat, it's kind of like graphite, the flatness of it. Any more questions before we kill this one?