A. Explain the difference between an exothermic chemical reaction and an endothermicchemical reaction. (1 point) B. How is the enthalpy of reaction related to the enthalpies of formation for the products and reactants? (1 point) C. What is Hess's law? (1 point) D. How does Hess's law use intermediate reactions to calculate the enthalpy of a desired reaction? (2 points) E. Mark each description as an exothermic or endothermic reaction. (2 points)