Question

Calculate the standard Gibbs free energy change for the following electrochemical reaction at 25°C:Cu(s) + 2Ag⁺(aq) → Cu²⁺(aq) + 2Ag(s) Given: E°cell = 0.46 V, F = 96,500 C/mol, R = 8.314 J/K·mol, and the standard reduction potentials at 25°C are Cu²⁺(aq) + 2e⁻ → Cu(s) (E°red = 0.34 V) and Ag⁺(aq) + e⁻ → Ag(s) (E°red = 0.80 V).

Answer 1

To calculate the standard Gibbs free energy change  G  for the given electrochemical reaction, we can use the following equation:G = -nFEcellwhere n is the number of moles of electrons transferred, F is the Faraday constant  96,500 C/mol , and Ecell is the standard cell potential.First, we need to determine the number of moles of electrons transferred  n  in the balanced reaction:Cu s  + 2Ag aq   Cu aq  + 2Ag s In this reaction, 2 moles of electrons are transferred from Cu to 2Ag. Therefore, n = 2.Now we can plug the values into the equation:G = -nFEcellG = - 2 mol  96,500 C/mol  0.46 V G = -88,760 J/molSince 1 kJ = 1,000 J, we can convert the result to kJ/mol:G = -88.76 kJ/molSo, the standard Gibbs free energy change for the given electrochemical reaction at 25C is -88.76 kJ/mol.