Which of the following statements is true for an exothermic reaction? the products have higher potential energy than the reactants, and the enthalpy change is negative. the products have higher potential energy than the reactants, and the enthalpy change is positive. the products have lower potential energy than the reactants, and the enthalpy change is negative. the products have lower potential energy than the reactants, and the enthalpy change is positive. what does a process require to be spontaneous at all temperatures? (2 points) a catalyst and lower activation energy a heat source and high activation energy positive enthalpy and negative entropy changes negative enthalpy and positive entropy changes