The amino acid glycine is often used as the main ingredient of a buffer in biochemical experiments. The amino group of glycine, which has a pKa of 9.6, can exist either in the protonated form (-NH3*) or as the free base (-NH2), because of the reversible equilibrium R-NH =R-NH2+ H* (a) In what pH range can glycine be used as an effective buffer due to its amino group? (b) In a 0.1 M glycine solution at pH 9.0, what fraction of glycine has its amino group in the -NH3* form? (c) When 99% of the glycine is in its -NH3* form, what is the numerical relation between the pH of the solution and the pKa of the amino group?

The amino acid glycine is often used as the main ingredient of a buffer in biochemical experiments. The amino group of glycine, which has a pKa of 9.6, can exist either in the protonated form (-NH3) or as the free base (-NH2), because of the reversible equilibrium R-NH =R-NH2+ H (a) In what pH range can glycine be used as an effective buffer due to its amino group? (b) In a 0.1 M glycine solution at pH 9.0, what fraction of glycine has its amino group in the -NH3* form? (c) When 99% of the glycine is in its -NH3* form, what is the numerical relation between the pH of the solution and the pKa of the amino group?

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

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