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Like any piece of apparatus, an electrolytic cell operates at less than100%efficiency. A cell depositingCufrom aCu2 +bath operates for10 hwith an average current of5.8 A. If53.4 gof copper is deposited, at what efficiency is the cell operating?

Short Answer

Expert verified

At 77.66%efficiency the cell is operating.

Step by step solution

01

Concept Introduction

An electrolytic cell is an electrochemical device that employs electrical energy to help a non-spontaneous redox reaction take place. Electrolytic cells are electrochemical cells that can be used to electrolyze a variety of substances.

A galvanic cell, or voltaic cell, is an electrochemical cell that converts the chemical energy of spontaneous redox reactions into electrical energy.

02

Information Provided

  • The reaction is Cu2 +(aq) + 2e-Cu(s)
  • The mass of Cu deposited is53.4 g
  • The Current is5.8A(A = C/s)
  • Cell is operated for10h(10h3600s1h= 3.6104s)
  • Faraday constant: charge of of electrons (F = 96485 C/mole)
03

Efficiency of the Cell

First find the charge 鈥

Current =ChargeTimeCharge = CurrentTime= 5.8 C/s3.6104s= 2.088105C

The number of moles of electrons is 鈥

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