40. In a galvanic cell, the cathode consists of a Ag"(1.00 M)|Ag half-cell. The anode is a platinum wire, with hydrogen bub- bling over it at 1.00-atm pressure, which is immersed in a buffer solution containing benzoic acid and sodium benzo- ate. The concentration of benzoic acid (C,H;COOH) is 0.10 M, and that of benzoate ion (C,H,COO") is 0.050 M. The overall cell reaction is then Ag* (aq) + H2(8) + H;O(t) → Ag(s) + H;O* (aq) and the measured cell potential is 1.030 V. Calculate the pH in the buffer solution and determine the K, of benzoic acid.

40. In a galvanic cell, the cathode consists of a Ag"(1.00 M)|Ag half-cell. The anode is a platinum wire, with hydrogen bub- bling over it at 1.00-atm pressure, which is immersed in a buffer solution containing benzoic acid and sodium benzo- ate. The concentration of benzoic acid (C,H;COOH) is 0.10 M, and that of benzoate ion (C,H,COO") is 0.050 M. The overall cell reaction is then Ag* (aq) + H2(8) + H;O(t) → Ag(s) + H;O* (aq) and the measured cell potential is 1.030 V. Calculate the pH in the buffer solution and determine the K, of benzoic acid.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter17: Electrochemistry

Section: Chapter Questions

Problem 76AP

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