Question

a. the activation energy of a reaction without an enzyme. b. the activation energy of a reaction with an enzyme. c. the total energy difference of the chemical reaction. d. the energy difference between the products and reactants. potential energy of molecules progress of reaction

Explanation:

The activation energy is the energy barrier that reactant molecules must overcome for a reaction to occur. In the graph, line A represents the energy difference between the reactants and the transition - state for a reaction without an enzyme. Enzymes lower the activation energy.

Answer:

A. the activation energy of a reaction without an enzyme.