Final answer:
Isomers are compounds that have the same molecular formula but different structural arrangements. To determine isomers, compare their structural arrangements. Isomers can have different physical and chemical properties even though they have the same molecular formula.
Step-by-step explanation:
Isomers are compounds that have the same molecular formula but different structural arrangements. To determine which pairs represent isomers, you need to compare their structural arrangements. Look for compounds with the same number and types of atoms but different connectivity or spatial arrangements.
For example, if you have two compounds with the same number of carbon, hydrogen, and oxygen atoms, but one has a straight chain while the other has a branched chain, they would be isomers.
Remember that isomers can have different physical and chemical properties even though they have the same molecular formula.