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20. Properties of a Buffer The amino acid glycine is often used as the main ingredient...
In a 0.1 M solution of glycine at pH 9.0, what fraction of glycine has its amino group in the -NH3+ form? I can't figure out how to get from 0.25=[NH2]/[NH3] to (0.25/[0.25+1]) x 100 = 20% Why do you divide by (0.25+1) ?
In a 0.1 M solution of glycine at pH 9.0, what fraction of glycine has its amino group in the —NH + 3 —NH3+ form? I know the answer, but can someone explain why the fraction is .25/(1+.25)) x100% = 20%? Where did the (1+.25) come from?
Suppose you have a peptide composed of 4 amino acids bonded together: glutamine, glycine, glutamic acid, and the novel amino acid friendsamine, which has an ionizable side group with a pKa of 5.9. At pH 7.0, this peptide has a net charge of -2. What is the charge on the protonated form of the friendsamine side group? Explain how you determined the charge on the protonated friendsamine side group
13. The amino acid histidine, Hist, is essential to the functioning of many proteins because it, and its protonated form HistH+, are components of the biochemical buffer equilibrium HistH(aq) + H20(I) <=> H30*(aq)+ Hist(aq), pka = 6.0 a. What is a pH of 1.0 L of a 0.10 M HistH(aq), 0.10 M Hist(aq). b. What is a pH of 1.0 L of a 0.10 M HistH(aq), 0.10 M Hist(aq)after 0.05 mol NaOH(s) is added to the buffer. Calculate the new...
Phosphate buffered saline (PBS) is a buffer solution commonly used in biological research. The buffer helps to maintain a constant pH. The osmolality and ion concentrations of the solution usually match those of the human body. A) You need to prepare a stock solution at pH 7.00 with KH2PO4 and Na2HPO4 (pKa =7.21). What would be the respective concentration of these substances if you wish to obtain the final phosphate concentration [HPO4 −2 ] + [H2PO4 − ] = 0.3...
Please justify each answer ! I would appreciate it eio, te -amino group 1s on the left, and thus the absolute configuration of the citrulline is I Relationship between the Titration Curve and the Acid-Base Properties of Glycine A 100 mL solution of 0.1 M glycine at pH 1.72 was titrated with 2 M NaOH solution. The pH was monitored and the results were plotted as shown in the following graph. The key points in the titration are designated I...
Consider the amino acid, glycine, in its fully protonated form + H3NCH2CO2H, where the pKa1 = 2.35 and pKa2 = 9.78. a) Ka2 is the equilibrium constant for the second dissociation of + H3NCH2CO2H. Write the chemical equation that illustrates this equilibrium. b) Write the structure for the major species at pH = 1.35. c) Write the structure for the major species at pH = 3.35. d) Write the structure for the major species at pH = 10.78. e) Calculate...
(10) (2) © © eg 2. Consider the amino acid, glycine, in its fully protonated form *H3NCH2CO2H, where the pka1 = 2.35 and pka2 = 9.78. a) Kaz is the equilibrium constant for the second dissociation of *H3NCH2CO2H. Write the chemical equation that illustrates this equilibrium. b) Write the structure for the major species at pH = 1.35. c) Write the structure for the major species at pH = 3.35. d) Write the structure for the major species at pH...
(10) (2) (2) 2. Consider the amino acid, glycine, in its fully protonated form *H3NCH2CO2H, where the pka1 = 2.35 and pka2 = 9.78. a) Kaz is the equilibrium constant for the second dissociation of H3NCH2CO2H. Write the chemical equation that illustrates this equilibrium. b) Write the structure for the major species at pH = 1.35. c) Write the structure for the major species at pH = 3.35. d) Write the structure for the major species at pH = 10.78....
HEPES is a commonly used biochemical buffer with a pKa 7.5 at 25 °C. Please answer the questions below on the use of HEPES as a buffer. Use the Henderson-Hasselbalch equation. a) What is the pH of a solution prepared by combining 100.0 mL of 0.50 M protonated HEPES with 50.0 mL of 0.20 M HEPES base and diluting to a final volume of 1.00 L? b) You add 20 mL of 1.0 M NaOH to the solution prepared in...