Moderate

Electrolysis of a solution MnSO4 in aqueous sulphuric acid is a method for the preparation of MnO2 passing a current of 27 A for 24 hours gives 1 kg of MnO2 .The current efficiency is:

Correct answer: B. 95.185%

  • A. 100%
  • B. 95.185%
  • C. 80%
  • D. 82.951%

Explanation

To calculate the current efficiency, we use Faraday's laws of electrolysis. First, calculate the theoretical yield of MnO2 using the formula:Theoretical mass of MnO2 = (It * M) / (n * F), where I is the current (27 A), t is the time in seconds (24 hours = 86400 seconds), M is the molar mass of MnO2 (86.94 g/mol), n is the number of electrons transferred per mole of MnO2 (2 for Mn2+ to MnO2), and F is Faraday's constant (96485 C/mol).Calculate the theoretical yield and compare it to the actual yield of 1 kg to find the efficiency:Efficiency (%) = (Actual yield / Theoretical yield) * 100.The correct answer, 95.185%, reflects the efficiency based on the calculated theoretical yield.Other options are incorrect as they do not match the efficiency calculated using the given data.

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