To calculate the standard free energy change G for the reaction, we first need to determine the overall standard cell potential E for the reaction. This can be done using the given standard reduction potentials.The balanced redox reaction is:MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2The reduction half-reaction is:MnO2 + 4H+ + 2e- -> Mn2+ + 2H2O E = -0.13 V The oxidation half-reaction is:2HCl -> Cl2 + 2H+ + 2e- E = 1.23 V Now, we can determine the overall standard cell potential E for the reaction by adding the standard reduction potentials:E cell = E reduction + E oxidation E cell = -0.13 V + 1.23 V E cell = 1.10 VNow that we have the standard cell potential, we can calculate the standard free energy change G using the following equation:G = -nFEwhere n is the number of moles of electrons transferred in this case, 2 , F is Faraday's constant 96,485 C/mol , and E is the standard cell potential.G = -2 * 96,485 C/mol * 1.10 VG = -212,267 J/molSince we typically express free energy changes in kJ/mol, we can convert this value:G = -212.27 kJ/molSo, the standard free energy change for the reaction of HCl with MnO2 to form MnCl2 and H2O at 298 K is -212.27 kJ/mol.