 Okay, so if you want to this one is actually the first problem on the quiz So if you want to check it out While you're working that'd be cool. If not, that's fine, too But it's asking Compute the total strain energy of the following confirmation using the values provided in the table And then it says show work for complete crit So if you look at this molecule if you're having a hard time Visualizing this molecule. I recommend that you build a model. I know sometimes building a model is time intensive, but I Don't know if you get practice building these things you can become really quick at them So this is the model of this molecule up here and remember we can rotate around This sigma bond here this carbon-carbon sigma bond and that's where this Table is coming from this Newman projection here. Okay, the particular Newman projection we have here is this one Okay, that's you can see the three methyls in front and then the one methyl in The back here, okay So if I asked you guys a question those of you are checking it out Is this Eclipse or staggered Staggered right okay, so when you look at the strain energy chart it kind of gives you Idea of which ones you're going to be dealing with straight away. Okay, so this one says eclipse eclipse eclipse So since it's not eclipsed you're not going to use any of those Everybody okay with my reasoning? So now we got a look for the Gouche ones, okay, and remember that's where the two big groups are 60 degrees away from each other So if we see we have the methyl group here in the hydrogen well, that's not going to show that interaction Okay, so we just go around and look for those Methyl group to a methyl group gouge. Yep. There's one of them So I like to mark it like that There's another one methyl group to methyl group gouge And then like we said, right there's no Interaction strain energy that is between the methyl and the hydrogen. Okay, so that's all there is doesn't anybody see anymore So I think that's it right so it's just 3.8 kilojoules per mole 3.8 kilojoules per mole and then the Problem of course asks you to work it out. So the energy strain energy Is going to be 3.8 kilojoules per mole plus 3.8 kilojoules per mole Are two times 3.8 kilojoules per mole and that gives you 7.6 kilojoules per mole. Okay, are there any questions on doing that type of a problem? Yes CH3 You would but they're not going to Okay, no strain energy involved. Okay. Any other questions? But yeah, consider anything that's within that table. Okay. Good question. Okay, cool