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What is the activation energy for the electrochemical reaction occurring between zinc and copper ions, given that the reaction has a rate constant of 1.5 x 10^-4 mol L^-1 s^-1 at 25°C and a rate constant of 6.2 x 10^-3 mol L^-1 s^-1 at 40°C?

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To calculate the activation energy  Ea  for the electrochemical reaction between zinc and copper ions, we can use the Arrhenius equation:k = A * exp -Ea /  R * T  where k is the rate constant, A is the pre-exponential factor, Ea is the activation energy, R is the gas constant  8.314 J mol^-1 K^-1 , and T is the temperature in Kelvin.We have two sets of data: k1 = 1.5 x 10^-4 mol L^-1 s^-1 at T1 = 25C  298.15 K  and k2 = 6.2 x 10^-3 mol L^-1 s^-1 at T2 = 40C  313.15 K .First, we can divide the two Arrhenius equations to eliminate the pre-exponential factor A:k2 / k1 = exp -Ea /  R * T2   / exp -Ea /  R * T1  Now, we can simplify the equation: k2 / k1  = exp Ea /  R * T1  - Ea /  R * T2  Taking the natural logarithm of both sides:ln k2 / k1  =  Ea / R  *  1 / T1 - 1 / T2 Now, we can solve for Ea:Ea = R * ln k2 / k1  /  1 / T1 - 1 / T2 Plugging in the values:Ea = 8.314 * ln 6.2 x 10^-3 / 1.5 x 10^-4  /  1 / 298.15 - 1 / 313.15 Ea  8.314 * ln 41.333  /  -0.000051 Ea  62.84 kJ/molThe activation energy for the electrochemical reaction occurring between zinc and copper ions is approximately 62.84 kJ/mol.

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