Final answer:
Isomers are compounds with the same molecular formula but differ in their structural formula. Structural isomers differ in covalent arrangement, while stereoisomers differ in spatial orientation. Functional isomers are a type of structural isomers with different functional groups.
Step-by-step explanation:
The question is asking to characterize the relationship between a pair of compounds based on their structures. Isomers are compounds that have the same molecular formula but different structural arrangements. There are multiple types of isomers, including structural isomers, which have a different covalent arrangement of atoms, and stereoisomers, which have the same sequence of bonded atoms but differ in how the atoms are oriented in space. Spatial isomers are a type of stereoisomer in which the relative orientations of the atoms in space differ without changing the sequence of atom bonding. Additionally, functional isomers are a subset of structural isomers that differ in the functional group attached to the molecule, giving them different chemical properties.
An example of structural isomerism is observed in the two pentane molecules that differ only in the location of the methyl group, while geometric and enantiomers are examples of stereochemistry. Understanding the various types of isomerism is essential for comprehending the diversity of molecular structures and their corresponding properties in chemistry.