In a chemical reaction, the difference between the potential energy of the products of the potential energy of the reactants is equal to the
a) activation energy
b) entropy of the system
c) heat of fusion
d) activation energy

Your question looks a bit incomplete as you have the same contents in options a) and d). According to your list, I can't see the correct answer, but I can give you one.The difference between the potential energy of the products of the potential energy of the reactants is equal to the enthalpy of the reaction.

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