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Calculate the enthalpy change of the reduction reaction of Fe3+ to Fe2+ when 1.44 g of Fe3+ ions are reduced using a standard hydrogen electrode (E° = 0.00 V) at 298 K. The balanced half-reaction equations are given below:Fe3+ + e- → Fe2+ ( E° = +0.77 V)H+ + e- → 1/2 H2(g) ( E° = 0.00 V)

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To calculate the enthalpy change of the reduction reaction of Fe3+ to Fe2+, we can use the Nernst equation and the relationship between Gibbs free energy change  G  and enthalpy change  H .First, we need to find the number of moles of Fe3+ ions in 1.44 g. The molar mass of Fe is 55.85 g/mol.moles of Fe3+ =  1.44 g  /  55.85 g/mol  = 0.0258 molNow, we can write the balanced redox reaction:Fe3+ + e-  Fe2+  E = +0.77 V 2H+ + 2e-  H2 g   E = 0.00 V The balanced redox reaction is:Fe3+ + 2H+ + e-  Fe2+ + H2 g The overall cell potential  E  is the difference between the reduction potential of the two half-reactions:E = E Fe3+/Fe2+  - E H+/H2  = 0.77 V - 0.00 V = 0.77 VNow, we can calculate the Gibbs free energy change  G  using the Nernst equation:G = -nFEwhere n is the number of moles of electrons transferred  in this case, n = 1 , F is the Faraday constant  96,485 C/mol , and E is the overall cell potential.G = - 1 mol  96,485 C/mol  0.77 V  = -74,293.45 J/molNow, we can use the relationship between Gibbs free energy change  G  and enthalpy change  H  at constant temperature:G = H - TSwhere T is the temperature in Kelvin  298 K  and S is the entropy change. Since we are only interested in the enthalpy change  H , we can rearrange the equation:H = G + TSUnfortunately, we don't have the entropy change  S  for this reaction. However, we can estimate the enthalpy change  H  using the Gibbs free energy change  G  as a rough approximation, assuming that the entropy change is not significant:H  G = -74,293.45 J/molNow, we can calculate the enthalpy change for the 0.0258 mol of Fe3+ ions:H =  -74,293.45 J/mol  0.0258 mol  = -1,915.57 JThe enthalpy change of the reduction reaction of Fe3+ to Fe2+ when 1.44 g of Fe3+ ions are reduced using a standard hydrogen electrode at 298 K is approximately -1,915.57 J.

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