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Calculate the standard free energy change for the following redox reaction: Balanced Chemical Equation: 2Fe3+(aq) +3H2O2(aq) → 2Fe2+(aq) + 3O2(g) + 6H+(aq)Given data: Standard reduction potential of Fe3+/Fe2+ = +0.77 V Standard reduction potential of H2O2/O2 = +0.70 V

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ago by (470 points)
To calculate the standard free energy change  G  for the redox reaction, we need to first determine the overall cell potential  Ecell  and then use the following equation:G = -nFEcellwhere n is the number of moles of electrons transferred, F is Faraday's constant  96,485 C/mol , and Ecell is the cell potential.First, we need to identify the half-reactions:Oxidation half-reaction: H2O2 aq   O2 g  + 2H+ aq  + 2e-Reduction half-reaction: Fe3+ aq  + e-  Fe2+ aq Now, we need to balance the half-reactions to find the overall redox reaction:Oxidation half-reaction  multiplied by 2 : 2H2O2 aq   2O2 g  + 4H+ aq  + 4e-Reduction half-reaction  multiplied by 4 : 4Fe3+ aq  + 4e-  4Fe2+ aq Adding the two balanced half-reactions, we get:2H2O2 aq  + 4Fe3+ aq   2O2 g  + 4H+ aq  + 4Fe2+ aq However, this is not the same as the given balanced chemical equation. To make it match, we need to multiply the oxidation half-reaction by 3 and the reduction half-reaction by 2:Oxidation half-reaction  multiplied by 3 : 3H2O2 aq   3O2 g  + 6H+ aq  + 6e-Reduction half-reaction  multiplied by 2 : 2Fe3+ aq  + 2e-  2Fe2+ aq Now, adding the two balanced half-reactions, we get the given balanced chemical equation:2Fe3+ aq  + 3H2O2 aq   2Fe2+ aq  + 3O2 g  + 6H+ aq Now we can find the overall cell potential  Ecell  using the standard reduction potentials given:Ecell = Ecathode - EanodeSince Fe3+ is being reduced, it is the cathode, and H2O2 is the anode:Ecell =  +0.77 V  -  +0.70 V  = +0.07 VNow we can calculate the standard free energy change  G  using the equation:G = -nFEcellThe number of moles of electrons transferred  n  is 6, as seen in the balanced equation:G = - 6 mol  96,485 C/mol  +0.07 V G = -40,560.9 J/molSince it is more common to express G in kJ/mol, we can convert the value:G = -40.56 kJ/molSo, the standard free energy change for the given redox reaction is -40.56 kJ/mol.

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