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Calculate the equilibrium constant for the following electrochemical reaction at 298K:$$\ce{2Fe^3+ (aq) + 2I^- (aq) -> 2Fe^2+ (aq) + I2 (s)}$$ Given: Standard reduction potentials: $\ce{Fe^3+ + e^- -> Fe^2+}$ Eº = +0.77V $\ce{2I^- -> I2 + 2e^- }$ Eº = +0.54V

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To calculate the equilibrium constant  K  for the given electrochemical reaction, we first need to determine the standard cell potential  E_cell  for the reaction. The standard cell potential can be calculated using the standard reduction potentials of the half-reactions:E_cell = E_cathode - E_anodeIn this case, the reduction half-reaction is:$\ce{Fe^3+ + e^- -> Fe^2+}$ with E = +0.77VThe oxidation half-reaction is:$\ce{2I^- -> I2 + 2e^- }$ with E = +0.54VSince the reduction potential of the iron half-reaction is greater than the iodine half-reaction, the iron half-reaction will act as the cathode and the iodine half-reaction will act as the anode.E_cell =  +0.77V  -  +0.54V  = +0.23VNow, we can use the Nernst equation to relate the standard cell potential to the equilibrium constant. The Nernst equation is:E_cell = -  RT/nF  * ln K Where R is the gas constant  8.314 J/molK , T is the temperature in Kelvin  298 K , n is the number of moles of electrons transferred in the balanced redox reaction  2 moles in this case , and F is the Faraday constant  96,485 C/mol .Rearranging the Nernst equation to solve for K, we get:ln K  = -  nFE_cell  /  RT Plugging in the values:ln K  = -  2 * 96,485 C/mol * 0.23V  /  8.314 J/molK * 298 K ln K   - 11.04To find K, we take the exponential of both sides:K = e^-11.04   1.63  10^-5 So, the equilibrium constant for the given electrochemical reaction at 298 K is approximately 1.63  10^-5 .

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