An experimental energy diagram for a certain reaction shows that the products are 120kJ lower in energy than the reactants. Which of the following best explains this difference in terms of average bond energies?
a) The 120kJ difference represents the activation energy of the reaction rather than bond‐energy changes.
b) The total energy released when product bonds form is 120kJ greater than the energy required to break the reactant bonds.
c) The energy required to break the reactant bonds is 120kJ greater than the energy released when the product bonds form.
d) Product bonds are weaker than reactant bonds, so forming them releases the extra 120kJ that lowers the products’ energy.