Introduction to Enthalpy Which of the following statements about an endothermic reaction are true? Check all that apply The solution containing an endothermic reaction will become warmer as the reaction proceeds. The size of the ΔH between reactants and products will change dramatically as the temperature changes The products represent a state of higher total energy. The products are less stable than the reactants. D The enthalpy of the reactants is higher than the enthalpy of the products. The reaction can not proceed to the products. Energy must be added in order to allow the reaction to proceed.