4.10 Consider a hydrogen fuel cell with 75% N2, 19% oxygen, and 6% H2O in the cathode at 1 atm total pressure. If the oxygen mole fraction is reduced because water vapor has been added to the cathode (new balance 15% O2, 25% H2O, and 60% N2), the expected OCV will fall. To counter this loss, you suggest changing the cathode pressure. To what value must your cathode total pressure be changed to in order to maintain the OCV? Conditions on the anode are not to be changed.

4.10 Consider a hydrogen fuel cell with 75% N2, 19% oxygen, and 6% H2O in the cathode at 1 atm total pressure. If the oxygen mole fraction is reduced because water vapor has been added to the cathode (new balance 15% O2, 25% H2O, and 60% N2), the expected OCV will fall. To counter this loss, you suggest changing the cathode pressure. To what value must your cathode total pressure be changed to in order to maintain the OCV? Conditions on the anode are not to be changed.

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter13: Electrochemistry

Section: Chapter Questions

Problem 13.106PAE: 13.106 Hydrazine, N2H4 , has been proposed as the fuel in a fuel cell in which oxygen is the...

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