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A solution containing 0.5 moles of potassium dichromate was electrolyzed with a current of 1.5 Amperes for 30 minutes. During the process, the final volume of the solution was found to be 250 mL. Calculate the value of the Faraday constant using this information.

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To calculate the Faraday constant, we need to first determine the number of moles of electrons transferred during the electrolysis process. Potassium dichromate  K2Cr2O7  undergoes reduction during electrolysis as follows:Cr2O7^2- + 14H^+ + 6e^-  2Cr^3+ + 7H2OFrom the balanced equation, we can see that 6 moles of electrons are required to reduce 1 mole of Cr2O7^2- ions.Since we have 0.5 moles of potassium dichromate in the solution, the number of moles of electrons required for the reduction is:0.5 moles K2Cr2O7 *  6 moles e^- / 1 mole Cr2O7^2-  = 3 moles e^-Next, we need to determine the total charge passed during the electrolysis process. We are given the current  1.5 Amperes  and the time  30 minutes . We can convert the time to seconds and then calculate the total charge:30 minutes *  60 seconds / 1 minute  = 1800 secondsTotal charge  Q  = Current  I  * Time  t Q = 1.5 A * 1800 s = 2700 CoulombsNow, we can calculate the Faraday constant  F  using the total charge  Q  and the number of moles of electrons  n :F = Q / nF = 2700 C / 3 moles e^-F  900 C/mol e^-The calculated value of the Faraday constant is approximately 900 Coulombs per mole of electrons. The actual Faraday constant is around 96485 C/mol e^-, so our calculated value is not accurate. This discrepancy could be due to experimental errors or assumptions made during the calculation.

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