Final answer:
Constitutional isomers are compounds with the same molecular formula but different structural arrangements of atoms, such as n-butane and 2-methylpropane, both with formula C4H10 but different atom connectivities.
Step-by-step explanation:
When identifying structures that represent compounds that are constitutional isomers of each other, it's important to understand that constitutional isomers have the same molecular formula but different sequences of bonds resulting in different structural arrangements.
An example of such isomers are the compounds n-butane and 2-methylpropane. N-butane has an unbranched chain of four carbon atoms, hence, all carbon atoms are bonded to at most two other carbon atoms.
In contrast, 2-methylpropane, while also containing four carbon atoms, has a branched structure where the central carbon atom is bonded to three other carbon atoms. Both compounds have the molecular formula C4H10, but their structures are not the same due to the different arrangement of their atoms.
To specifically identify constitutional isomers of each other, we must look for compounds with identical molecular formulas that exhibit different bonding sequences leading to various skeletal, functional group, or positional isomers.
The complete question is: Which of the following structures represent compounds that are constitutional isomers of each other?