Write condensed and bond-line structural formulas for all of the constitutional isomers Practice problem 4.1 with the molecular formula C7H16. (There are a total of nine constitutional isomers.)

See figure 1.

Explanation:

In this case have to take into account that all structures must have the formula: . If we remember the general formula for alkanes: if we have "7" carbons (n=7) we will have 16 hydrogens.  Therefore all the structures that fit with this formula are alkanes.

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