Which of the following processes is represented by an energy diagram where the products have lower energy than the reactants?

• A. A reaction at equilibrium
• B. A decomposition reaction
• C. An exothermic reaction
• D. An endothermic reaction

Answer: (C)

Verified step by step guidance

1. Understand that an energy diagram shows the relative energy levels of reactants and products during a chemical reaction.
2. Recall that if the products have lower energy than the reactants, the reaction releases energy to the surroundings.
3. Recognize that a reaction releasing energy is called an exothermic reaction.
4. Contrast this with an endothermic reaction, where products have higher energy than reactants because energy is absorbed.
5. Conclude that the process represented by an energy diagram with products at lower energy than reactants is an exothermic reaction.