A. Phosphate Buffer 1. Prepare 100 mL of a 0.01 M phosphate buffer, pH 7.70, from stock solutions of 0.1 M K2HPO4and 0.2 M KH2PO4. (pKa for the weak acid = 7.20). a. Use the Henderson-Hasselbalch equation to calculate the volume of each stock solution needed. pH = RKa + log [conjugate base] / [weak acid] b. Check your calculations with other students. See the instructor if there is uncertainty. c. Make the solution and check the pH of a portion of your buffer solution using the pH meter.

A. Phosphate Buffer 1. Prepare 100 mL of a 0.01 M phosphate buffer, pH 7.70, from stock solutions of 0.1 M K2HPO4and 0.2 M KH2PO4. (pKa for the weak acid = 7.20). a. Use the Henderson-Hasselbalch equation to calculate the volume of each stock solution needed. pH = RKa + log [conjugate base] / [weak acid] b. Check your calculations with other students. See the instructor if there is uncertainty. c. Make the solution and check the pH of a portion of your buffer solution using the pH meter.

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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