Radioactive isotopes are often used as “tracers” to follow an atom through a chemical reaction. The following is an example of this process: Acetic acid reacts with methanol, CH₃OH, by eliminating a molecule of H₂O to form methyl acetate, CH₃CO₂CH₃. Explain how you would use the radioactive isotope ¹⁵O to show whether the oxygen atom in the water product comes from the —OH of the acid or the —OH of the alcohol.