Explain the difference between an endothermic and an exothermic reaction using the concepts of potential energy, stability, and a system. How do these types of reactions demonstrate the conservation of energy? (Energy of Reactions)

An Exothermic reaction releases energy into the surroundings and so the products have more potential energy then the reactants. The enthalpy change is a negative value. Whereas, an endothermic reaction involves the absorption of energy into the system and so the reactants have more potential energy than the products. The enthalpy change is a positive value. This is clearly represented in energy profile diagrams.