Phosphate buffer solutions are commonly used in biology because they allow to cover a large range of pH comprised between pH 5.8 and pH 8. They are usually made by mixing suitable volumes of KH2PO4 (potassium dihydrogen phosphate) and K₂HPO4 (dipotassium hydrogen phosphate) solutions, using the Henderson- Hasselbalch equation. Data: pKa = 7.2 for the equilibrium considered in the problem 1- Give the Henderson-Hasselbalch equation. 2- Indicate how to prepare Vf = 100 mL of phosphate buffer solution of final total phosphate concentration C₁ = 0.1 M and pH 7.2, using stock solutions of KH₂PO4 and K₂HPO4 both at Co = 0.5 M.

Phosphate buffer solutions are commonly used in biology because they allow to cover a large range of pH comprised between pH 5.8 and pH 8. They are usually made by mixing suitable volumes of KH2PO4 (potassium dihydrogen phosphate) and K₂HPO4 (dipotassium hydrogen phosphate) solutions, using the Henderson- Hasselbalch equation. Data: pKa = 7.2 for the equilibrium considered in the problem 1- Give the Henderson-Hasselbalch equation. 2- Indicate how to prepare Vf = 100 mL of phosphate buffer solution of final total phosphate concentration C₁ = 0.1 M and pH 7.2, using stock solutions of KH₂PO4 and K₂HPO4 both at Co = 0.5 M.

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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