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What is the Gibbs free energy change for the electrochemical reaction when a copper electrode is placed in a 1 M copper(II) sulfate solution and a standard hydrogen electrode (SHE) is placed in a 1 M hydrogen ion solution at 25°C?

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To calculate the Gibbs free energy change  G  for the electrochemical reaction between a copper electrode in a 1 M copper II  sulfate solution and a standard hydrogen electrode  SHE  in a 1 M hydrogen ion solution at 25C, we need to use the following equation:G = -nFEwhere n is the number of moles of electrons transferred in the reaction, F is the Faraday constant  96,485 C/mol , and E is the cell potential.First, we need to determine the cell potential  E  for the reaction. The cell potential can be calculated using the Nernst equation:E = E -  RT/nF  * ln Q where E is the standard cell potential, R is the gas constant  8.314 J/molK , T is the temperature in Kelvin  25C = 298 K , and Q is the reaction quotient.For the given reaction, the half-reactions are:1. Cu + 2e  Cu  reduction 2. 2H + 2e  H  oxidation The standard reduction potential  E  for Cu/Cu is +0.34 V, and for the SHE  H/H , it is 0 V by definition. Since the copper electrode is being reduced and the hydrogen electrode is being oxidized, the overall cell potential  E  is:E = E Cu/Cu  - E H/H  = 0.34 V - 0 V = 0.34 VSince both the copper II  sulfate and hydrogen ion solutions have a concentration of 1 M, the reaction quotient  Q  is:Q = [Cu][H]/[H] =  1  1 / 1  = 1Now we can calculate the cell potential  E  using the Nernst equation:E = E -  RT/nF  * ln Q  = 0.34 V -  8.314 J/molK * 298 K /  2 * 96,485 C/mol   * ln 1 Since ln 1  = 0, the cell potential  E  remains 0.34 V.Finally, we can calculate the Gibbs free energy change  G  using the equation:G = -nFE = - 2 mol  96,485 C/mol  0.34 V  = -65,609.4 J/molSo, the Gibbs free energy change for the electrochemical reaction is -65,609.4 J/mol.

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