Figure 2.2. Flowchart of Isomer Relationships
Physical and chemical properties are prime MCAT material and are often tested in the context of
isomerism. Physical properties are characteristics of processes that don’t change the composition
of matter, such as melting point, boiling point, solubility, odor, color, and density. Chemical
properties have to do with the reactivity of the molecule with other molecules and result in changes
in chemical composition. In organic chemistry, the chemical properties of a compound are generally
dictated by the functional groups in the molecule.
KEY CONCEPT
Physical properties: no change in composition of matter; examples include melting point,
boiling point, solubility, odor, color, density.
Chemical properties: reactivity of molecule, resulting in change in composition; generally
attributable to functional groups in the molecule.
MCAT Concept Check 2.1:
Before you move on, assess your understanding of the material with these questions.
What property or properties do structural isomers have in common?