Final answer:
Reducing agent atoms are located on the left side of the energy potential equations as they are the reactants that undergo oxidation by donating electrons during a chemical reaction.
Step-by-step explanation:
Reducing agent atoms will be on the left side of the energy potential equations as part of the reactants. In a chemical reaction, reducing agents donate electrons, undergoing oxidation themselves, while oxidizing agents accept electrons, undergoing reduction. Since both the oxidizing and reducing agents are reactants in a chemical reaction, they are placed on the left-hand side of the chemical equation before the reaction occurs.