a- For the reaction: Zn(s) + 2H (aq) → Zn (aq) + H₂ (g) [Ez=-0.7628 V, EH120.000] Calculate the change in free energy AG for the reaction? b- The cell Pt/H₂ (1 bar.)/HBr (m)/ AgBr / Ag in the following table gives the electromotive forces obtained at 25 °C. m (mol. Kg 0.01 ') 0.01 0.05 0.10 E(V) 0.3127 0.2786 0.2340 0.2005 Calculate 1- E and 2- the activity coefficient for a 0.10 mol kg solution of hydrogen bromide.

a- For the reaction: Zn(s) + 2H (aq) → Zn (aq) + H₂ (g) [Ez=-0.7628 V, EH120.000] Calculate the change in free energy AG for the reaction? b- The cell Pt/H₂ (1 bar.)/HBr (m)/ AgBr / Ag in the following table gives the electromotive forces obtained at 25 °C. m (mol. Kg 0.01 ') 0.01 0.05 0.10 E(V) 0.3127 0.2786 0.2340 0.2005 Calculate 1- E and 2- the activity coefficient for a 0.10 mol kg solution of hydrogen bromide.

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter18: Electrochemistry

Section: Chapter Questions

Problem 18.52QE

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