Final answer:
An exothermic reaction is the opposite of an endothermic reaction, as it releases energy, whereas an endothermic reaction absorbs energy from the surroundings.
Step-by-step explanation:
In terms of energy, an exothermic reaction is the opposite of an endothermic reaction. While an exothermic reaction involves the release of energy to the surroundings, typically as heat, an endothermic reaction absorbs energy from its surroundings. During an exothermic reaction, the products have a lower energy level compared to the reactants because the bonds in the product are stronger and more energy is released than is absorbed during the formation of these bonds. The loss of energy by the system results in the increase in temperature of the surroundings. Conversely, in an endothermic reaction, energy is absorbed to break bonds in the reactants, resulting in higher energy products.