The standard electrode potentials for the reduction of N2 to N2H4 and of O2 to H2O at 298 K are –1.155 V and +0.401 V, respectively, both under alkaline conditions. (i) Write a balanced equation for both of the half cell reactions under alkaline conditions. For the cell reaction where the hydrazine electrode is on the left, calculate the standard EMF of the cell at 298 K. (ii) In a practical cell the concentrations of N2H4 and OH- are 0.5 M and 1.0 M, respectively, and the pressure of O2 and N2 are 0.2 bar and 0.8 bar, respectively. Use the Nernst equation to estimate the cell EMF at 298 K, assuming all activity coefficients are unity.

The standard electrode potentials for the reduction of N2 to N2H4 and of O2 to H2O at 298 K are –1.155 V and +0.401 V, respectively, both under alkaline conditions. (i) Write a balanced equation for both of the half cell reactions under alkaline conditions. For the cell reaction where the hydrazine electrode is on the left, calculate the standard EMF of the cell at 298 K. (ii) In a practical cell the concentrations of N2H4 and OH- are 0.5 M and 1.0 M, respectively, and the pressure of O2 and N2 are 0.2 bar and 0.8 bar, respectively. Use the Nernst equation to estimate the cell EMF at 298 K, assuming all activity coefficients are unity.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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