What does the difference in potential energy between the reactants and products represent?

The difference in potential energy between the reactants and products represent present the change in enthalpy for the reaction. The disparity in enthalation between the reactants and the components is equal to the energy released to the surroundings. An exothermic reaction is a reaction in which energy is released to the surroundings. In endothermic reactions product enthalpy is greater than reactant enthalpy.