Final answer:
Hydrocarbons can differ in their structure due to branching, double bonds, ring structures, and chain length.
Step-by-step explanation:
Hydrocarbons with the same formula can have different structures. For example, one hydrocarbon can be branched, meaning it has carbon branches attached to the chain. Another hydrocarbon can have a double bond, which changes the geometry of the molecule. A third hydrocarbon can have a ring structure, such as benzene. Lastly, one hydrocarbon can be longer than the other, meaning it has more carbon atoms in its chain.