Which of the following best describes what happens during an exothermic reaction?

• A. The products have higher energy than the reactants.
• B. No energy change occurs between the reactants and products.
• C. Energy is released to the surroundings, usually in the form of heat.
• D. Energy is absorbed from the surroundings, causing the temperature to decrease.

Answer: (C)

Verified step by step guidance

1. Understand the definition of an exothermic reaction: it is a chemical reaction that releases energy to the surroundings.
2. Recall that energy changes during a reaction are related to the difference in energy between reactants and products.
3. In an exothermic reaction, the products have lower energy than the reactants because excess energy is released.
4. This released energy is often observed as heat, which increases the temperature of the surroundings.
5. Therefore, the best description is that energy is released to the surroundings, usually in the form of heat.