Draw the structural formulas and name all cyclic isomers with the formula C₅H₁₀.

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Hi, everyone. Our next problem says name and provide the line structures of possible constitutional isomers of a cyclic Alcaine with a formula of C six H 12 and an ethyl substituent. So when we think about constitutional isomers, we need to recall that these are isomers where the formula is the same, which makes sense since we're provided with a formula, but the linkage is different, we're given a formula and we know that we have six carbons total, but two of the carbons must be on a substituent. And we also know that we have a ring, we have a cyclic alkene. So if two of our carbons are in a branch, that means the highest number of carbons we can have in the ring is four since we have six total. So our first constitutional isomer would involve a four carbon ring which would be a square. So there's four of our carbons and then an ethyl substituent 12 carbon branch coming off of that, we don't need to number the branch in our name because all positions are equivalent here. So we just have Ethel for our ethyl branch and then Cyclo butane since its a four carbon ring. So that's our first structural isomer. However, we can have a ring with only three carbons. So we could have a ring with three carbons in ethyl group. And then the last carbon in a methyl group. So that would be a triangular shape. And then we have an ethel group coming off one corner and let's put our methyl group on another corner. There's only one arrangement of this because obviously, if we put the methyl group over here, it would just be the same molecule. So we could number it either with the methyl group on carbon one or the ethyl group on carbon one. So we just go in alphabetical order, ethyl comes first. So we make ethyl the group on carbon one. So one ethyl and then two methyl, our ring has three carbons. So it's propane. So one ethyl, two methyl propane, but we've got one other possible arrangement with a three carbon ring if we put both of those groups on the same carbon. So let's draw a three carbon ring and put our methyl group and our ethyl group both on the same carbon. So we end up with one ethyl, one methyl propane, we can't go any smaller, nothing smaller will be a ring which we're told we have. So we've got our four carbon ring and 23 carbon rings. So our possible structural isomers and our names, we have ethyl cyclo butane, four carbon ring with an ethyl group, one ethyl, two methyl propane and one ethyl, one methyl propane. Both of which are three carbon rings with an ethyl group and a methyl group, one on two different carbons and one where both are on the scene. See you in the next video.

Draw the structural formulas and name all cyclic isomers with the formula C₅H₁₀.

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Draw the structural formulas and name all cyclic isomers with the formula C₅H₁₀.