part b in this reaction . a scheme of a chemical reaction. the reactants are two molecules, one of which consists of a and b, and the other consists of c and d. the products are two molecules, one of which consists of a and c, and the other consists of b and d. the energy of molecules ab and cd is higher than the energy of molecules ac and bd. in this reaction . a scheme of a chemical reaction. the reactants are two molecules, one of which consists of a and b, and the other consists of c and d. the products are two molecules, one of which consists of a and c, and the other consists of b and d. the energy of molecules ab and cd is higher than the energy of molecules ac and bd. the chemical energy of the products is greater than that of the reactants disorder has decreased heat has been released to the environment the kinetic energy of the reactants is less than that of the products entropy has decreased