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Calculate the standard Gibbs free energy change for the electrochemical reaction of zinc and copper ions: Zn(s) + Cu2+(aq) → Cu(s) + Zn2+(aq)Given the following standard electrode potentials: E°(Cu2+(aq) + 2e- → Cu(s)) = 0.34 V E°(Zn2+(aq) + 2e- → Zn(s)) = -0.76 V Assume standard conditions (25°C and 1 atm pressure) and that the concentrations of the copper and zinc ions are both 1 mol/L.

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To calculate the standard Gibbs free energy change  G  for the electrochemical reaction, we first need to determine the standard cell potential  E  for the reaction. This can be found by subtracting the standard electrode potential of the reduction half-reaction from the standard electrode potential of the oxidation half-reaction.The given standard electrode potentials are:E Cu2+ aq  + 2e-  Cu s   = 0.34 V  reduction half-reaction E Zn2+ aq  + 2e-  Zn s   = -0.76 V  reduction half-reaction Since Zn is oxidized in the reaction, we need to reverse the Zn half-reaction to make it an oxidation half-reaction:E Zn s   Zn2+ aq  + 2e-  = +0.76 V  oxidation half-reaction Now we can calculate the standard cell potential  E  for the overall reaction:E cell  = E reduction  - E oxidation  = 0.34 V -  -0.76 V  = 1.10 VNext, we can use the relationship between the standard cell potential and the standard Gibbs free energy change:G = -nFEwhere n is the number of moles of electrons transferred in the reaction  in this case, 2 moles of electrons , F is Faraday's constant  96,485 C/mol , and E is the standard cell potential.G = - 2 mol  96,485 C/mol  1.10 V  = -212,267 J/molSince the standard Gibbs free energy change is typically expressed in kJ/mol, we can convert the units:G = -212,267 J/mol *  1 kJ/1000 J  = -212.27 kJ/molSo, the standard Gibbs free energy change  G  for the electrochemical reaction of zinc and copper ions is -212.27 kJ/mol.

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