In this chapter, we covered the essential MCAT topic of oxidation—reduction reactions. We reviewed the rules for assigning oxidation numbers to help us keep track of the movement of electrons from the species that are oxidized (reducing agents) to the species that are reduced (oxidizing agents). We also covered the sequence of steps involved in balancing half-reactions, redox titrations, and disproportionation reactions.
In addition to understanding the fundamental chemical principles behind these reactions, you will begin to see these concepts resurface in MCAT Organic Chemistry Review and MCAT Biochemistry Review. Oxidation—reduction reactions are often used for energy transfer in biological systems, and any deficiencies in such systems are profoundly deleterious (such as metabolic, mitochondrial, and immunologic diseases). Our next chapter—the last of MCAT General Chemistry Review—brings the principles of oxidation—reduction reactions to their application in electrochemical cells. By the end of the next chapter, you will have reviewed all of the general chemistry knowledge required for Test Day!