To calculate the overpotential, we first need to determine the equilibrium potential E of the electrochemical reaction. However, the information provided is not sufficient to determine the equilibrium potential directly. In general, overpotential is the difference between the electrode potential E and the equilibrium potential E : = E - EGiven the information provided, we can only determine the difference in overpotential between the two measurements: = E1 - E - E2 - E = E1 - E2 = -0.6 V - -0.5 V = -0.1 VThis means that the overpotential has changed by 0.1 V between the two measurements, but we cannot determine the exact overpotential for the reaction without knowing the equilibrium potential E . The student would need to provide more information about the electrochemical reaction to determine the overpotential accurately.