Draw structures for all constitutional isomers with the following molecular formula: C6H14

Constitutional isomers, also called structural isomers, are molecules that have the same molecular formula but different structure.

In our case, the molecular formula is C₆H₁₄. All of the constitutional isomers must have six carbons and fourteen hydrogens.

1. We can begin by drawing a six carbon chain. Hydrogens are not drawn but implied in the line angle structure. You could also show all the carbons and hydrogens if that is easier.
2. We can then shorten a chain by one carbon and add it to the other part of the chain creating a constitutional isomer. We can add it to the second or third carbon.
3. We shorten the parent chain by another carbon and draw a four carbon chain. Now we need to add two carbons to it. We can add both carbons to the second carbon, or we can add one carbon to the second carbon and one carbon to the third carbon.

Please note, we can not add carbons to the ends of the parent chain because it would recreate the same molecule. For example starting with a five carbon chain and adding another carbon to the end brings us to the six carbon chain which we already had.

Here are all of the constitutional isomers of hexane.

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