Chemistry
10th Edition
ISBN: 9781305957404
Author: Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher: Cengage Learning
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Textbook Question
Chapter 15, Problem 90AE
a. Calculate the pH of a buffered solution that is 0.100 M in C6H5CO2H (benzoic acid, Ka = 6.4 × 10−5) and 0.100 M in C6H5CO2Na.
b. Calculate the pH after 20.0% (by moles) of the benzoic acid is converted to benzoate anion by addition of a strong base. Use the dissociation equilibrium
C6H5CO2H(aq) ⇌ C6H5CO2-(aq) + H+(aq)
to calculate the pH.
c. Do the same as in part b, but use the following equilibrium to calculate the pH:
C6H5CO2-(aq) + H2O(l) ⇌ C6H5CO2H(aq) + OH-(aq)
d. Do your answers in parts b and c agree? Explain.
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Chapter 15 Solutions
Chemistry
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