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What is the equilibrium constant (Kc) for the reaction between potassium permanganate (KMnO4) and sulfur dioxide (SO2) in aqueous solution, given that sulfur dioxide is a weak reducing agent? Calculate the value of Kc at a temperature of 298 K.

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To calculate the equilibrium constant  Kc  for the reaction between potassium permanganate  KMnO  and sulfur dioxide  SO  in aqueous solution, we first need to write the balanced chemical equation for the reaction. The reaction can be written as:2 KMnO + 5 SO + 2 HO  2 MnSO + KSO + 5 HSOHowever, we cannot directly calculate the value of Kc without any experimental data or standard electrode potentials. Instead, we can use the Nernst equation to find the standard cell potential  E  and then use it to calculate the equilibrium constant  Kc .The Nernst equation is given by:E = E -  RT/nF  * lnQwhere E is the cell potential, E is the standard cell potential, 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 reaction, F is the Faraday constant  96,485 C/mol , and Q is the reaction quotient.To find the standard cell potential  E , we need the standard electrode potentials for the two half-reactions:1. Reduction of permanganate ion  MnO  to manganese II  ion  Mn :MnO + 8 H + 5 e  Mn + 4 HO; E = 1.51 V2. Oxidation of sulfur dioxide  SO  to sulfate ion  SO :2 SO + 2 HO  SO + 4 H + 2 e; E = -0.17 VNow, we can find the standard cell potential  E  for the overall reaction by subtracting the standard electrode potential of the oxidation half-reaction from the standard electrode potential of the reduction half-reaction:E = E - E = 1.51 V -  -0.17 V  = 1.68 VSince the Nernst equation relates the cell potential  E  to the equilibrium constant  Kc , we can rearrange the equation to solve for Kc:E = E -  RT/nF  * lnQAt equilibrium, E = 0 and Q = Kc, so:0 = E -  RT/nF  * lnKcNow, we can solve for Kc:lnKc =  nFE / RT Kc = e^ nFE / RT  For our reaction, n = 5  5 moles of electrons are transferred in the reaction . Plugging in the values, we get:Kc = e^ 5 * 96,485 C/mol * 1.68 V  /  8.314 J/molK * 298 K  Kc  2.17  10So, the equilibrium constant  Kc  for the reaction between potassium permanganate  KMnO  and sulfur dioxide  SO  in aqueous solution at 298 K is approximately 2.17  10.

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