6 The titration curve of alanine shows the ionization of two functional groups with pK, values of 2.34 and 9.69, corresponding tothe ionization of the carboxyl and the protonated amino groups, respectively. The titration of di-, tri-, and larger oligopeptides ofalanine also shows the ionization of only two functional groups, although the experimental pK, values are different. The tablesummarizes the trend in pka values.Amino acid or peptidepKIpk2Ala2.349.69Ala-Ala3.128.30Ala-Ala-Ala3.398.03Ala-(Ala),-Ala, n 2 43.427.94Modify the molecules to show the oligopeptide Ala-Ala-Ala. You can modify the molecules by moving, adding, deleting.or changing atoms, bonds, or charges.SelectDrawRingsMoreEraseH -N -C - CCH,H.CH,HCH,HComplete the statements about the the pKa values of the Ala-Ala-Ala oligopeptide.

The titration curve of alanine shows the ionization of two functional groups with pK, values of 2.34 and 9.69, corresponding to the ionization of the carboxyl and the protonated amino groups, respectively. The titration of di-, tri-, and larger oligopeptides of alanine also shows the ionization of only two functional groups, although the experimental pK, values are different. The table summarizes the trend in pK, values. Amino acid or peptide pki pk2 Ala 2.34 9.69 Ala-Ala 3.12 8.30 Ala-Ala-Ala 3.39 8.03 Ala-(Ala),-Ala, n 2 4 3.42 7.94 Modify the molecules to show the oligopeptide Ala-Ala-Ala. You can modify the molecules by moving, adding, deleting. or changing atoms, bonds, or charges. Select Draw Rings More Erase H -N - 1. CH, H. CH, H. CH,

The titration curve of alanine shows the ionization of two functional groups with pK, values of 2.34 and 9.69, corresponding to the ionization of the carboxyl and the protonated amino groups, respectively. The titration of di-, tri-, and larger oligopeptides of alanine also shows the ionization of only two functional groups, although the experimental pK, values are different. The table summarizes the trend in pK, values. Amino acid or peptide pki pk2 Ala 2.34 9.69 Ala-Ala 3.12 8.30 Ala-Ala-Ala 3.39 8.03 Ala-(Ala),-Ala, n 2 4 3.42 7.94 Modify the molecules to show the oligopeptide Ala-Ala-Ala. You can modify the molecules by moving, adding, deleting. or changing atoms, bonds, or charges. Select Draw Rings More Erase H -N - 1. CH, H. CH, H. CH,

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter16: Reactions Between Acids And Bases

Section: Chapter Questions

Problem 16.66QE: Write the chemical equilibrium and expression for the equilibrium constants for the ionization of...

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Write the chemical equilibrium and expression for the equilibrium constants for the ionization of (a) tartaric acid. (b) malic acid.
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Sketch a titration curve for the amino acid cysteine, and indicate the pKavalues for all titratable groups. Also, indicate the pH at which cysteinehas no net charge.
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Give typed full explanation not a single word hand written otherwise leave it Calculate the isoelectric point of the amino acid histidine by plotting the titration curve. (pka values α-COOH=1.82, α-NH2= 9.17, imidazole= 6.0)
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A student added a total of 75 mL sodium hydroxide to titrate an amino acid solution with 0.5M NaOH. They also calculated that they added a total of 14 mL of sodium hydroxide to arrive at pH 2.6 and a total of 32 mL of sodium hydroxide to arrvive at pH 4.8.What was the initial concentration of the amino acid solution in milimolar (mM)? The calculations must be presented such that those can be recapitulated by the marker. Provide the answer with no decimal places. Show all details of your working out. State the answer in a full sentence.
For the amino acid alanine, the major species in solution at pH 7 is the zwitterionic form, which has a negatively charged carboxylic acid group and a positively charged amino group. There is a less common neutral form in which neither group is charged. The carboxylic acid group of alanine has a p?a of 3 The amino group of alanine has a p?a of 8 Estimate the ratio of the concentration of the neutral amino acid species to the zwitterionic species at pH 7. __?__x10^?
The activity of an enzyme requires a glutamic acid to display its -COOH functional group in the protonated state. Suppose the pK, of the -COOH group is 4.07. (a) Will the enzyme be more active at pH 3.5 or 4.5? Explain. (b) What fraction of the enzymes will be active at pH = 4.07? Explain. (c) At what pH will the enzyme show 78% of maximal activity?