Compounds having the same molecular formula but different structures (manners in which atoms are linked) are classified as structural isomers. This includes chain isomers, position isomers, functional group isomers and metamerism.

For the given compound, ${\mathrm{C}}_6{\mathrm{H}}_{14}$, different structural isomers are possible, which are chain or position isomers of each other. The isomers are given below.



Therefore, the compound ${\mathrm{C}}_6{\mathrm{H}}_{14}$ has a total of 5 structural isomers.