28. Answer the following questions to find the mass (g) of dipotassium phthalate must be added to 250 mL of 0.0250 M phthalic acid to give a buffer of pH 5.75? MW K2P = 242.32 g/mol Ka2 = [H30^+] [P^-] / [HP^-] = 3.91 x 10^-6 What is the amount of P^2- needed in the buffer? 164.92 mmol 82.46 mmol 53.88 mmol 27.49 mmol

28. Answer the following questions to find the mass (g) of dipotassium phthalate must be added to 250 mL of 0.0250 M phthalic acid to give a buffer of pH 5.75? MW K2P = 242.32 g/mol Ka2 = [H30^+] [P^-] / [HP^-] = 3.91 x 10^-6 What is the amount of P^2- needed in the buffer? 164.92 mmol 82.46 mmol 53.88 mmol 27.49 mmol

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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