There are two branched-chain isomers with the formula C₇H₁₆, w...

Question

There are two branched-chain isomers with the formula C₇H₁₆, where the longest chain in the molecule is six carbons long. Draw them.

Accepted Answer

All right. Hi, everyone. So this question says to consider the formula C six H 14, draw the two branched chain isomers or the longest chain is four carbons long. So before we get into the question, I want to make sure of something, right? And that is whether or not the compounds we are to draw are all canes or not, right? Recall that all canes are organic compounds that contain only carbon carbon, single bonds and all canes have a molecular formula of CN H two N added to two. And so the reason why I want to bring this up is because if the molecular formula I'm given matches the general formula for an all cane, I can confirm whether or not this compound does or does not have double bonds, triple bonds or any sort of ring structure. So let me check this because the number of carbons in the molecular formula given is six N is equal to six, right? So that's C six H oops my bad H two multiplied by six added to two. So when I simplify this, I do in fact, get C six H 14. So because the molecular formula given matches the general formula of an all cane. There are no double bonds, no trouble ones and no ring structures either. So this is simply going to be an old king. So now we can proceed with the actual drawing. And I'm going to start off with our 24 carbon chains, right? Because we have two branched chain isomers and the longest chain is four carbons long. So I'm going to start by drawing out four carbons in a street che because both eye swimmers have to be branched, right. We're going to have substituents attaching to the parent chain, but not necessarily part of it. So because there are six carbons in total four consisting or making up the parent chain, this means I can add two more carbons as substituents. So I have two possibilities. I could potentially make a two carbon substituent. But the problem with this is that the longest carbon chain present in the molecule would actually be five carbons long as opposed to four, right. So this is not going to be a possibility. Instead, we're going to have 21 carbon substituents present in the molecule. However, if I were to place the one carbon substituents on positions one or four, then that would also extend the parent chain, right, make it longer than four carbons. So instead I'm going to place my substituents on carbons two and three. So that's one possibility, right? But the other possibility is I can take the same four carbon chain and add my two substituents onto the same carbon, namely carbon two. So now these are the carbon skeletons of our isomers. So our last step is to go ahead and add our hydrogens. Recall, carbon prefers to have four covalent bonds whereas hydrogen only prefers to have one. So in this case, considering each carbon atom, hydrogen is going to compensate for the number of bonds that each carbon out of is missing. So if I consider carbon one of each isomer, because carbon one is connected to only one other carbon, this means that they are going to require three covalent bonds to hydrogen atoms. And the same is true for our substituents. So at that point, I would go ahead and add all hydrogen to each carbon, make sure all of them have four covalent bonds. I'm going to extend this a little bit just so that the hydrogens are a bit easier to see referring to the second or rather the substituent here on carbon tube for the first isomer. So now we can do the same thing for the second isomer, right? If each carbon here has only one bond to another carbon, that that means that three hydrogens are required to make sure that it has the four covalent bonds that it prefers, right? If a carbon has two covalent bonds to other carbons, then that means that two hydrogens are required. And if one carbon already has four bonds to other carbons, then no hydrogens are needed for that one. And there you have it right here are the two branched chain isomers with the molecular formula of C six H 14. And with the longest carbon chain being four carbons long. So if you stuck around to the end, thank you so very much for watching. And I hope you found this helpful.

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There are two branched-chain isomers with the formula C₇H₁₆, where the longest chain in the molecule is six carbons long. Draw them.

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