1. a) Classify the amino acids according to the nature of their side chains (R groups), stating which are polar, non-polar, acidic and basic. Draw the structure of the amino acid glutamic acid in neutral solution at pH7.0. b) What is meant by the term isoelectric point of an amino acid? Discuss how is it related to the pKa values of an amino acid? c) What practical technique would you use to separate a mixture of the amino acids arginine, valine and glutamic acid? State briefly how it works. d) Describe in detail the two analytical methods that can be used to separate a complex mixture of proteins, yielding individual proteins with different amino acid sequences.

1. a) Classify the amino acids according to the nature of their side chains (R groups), stating which are polar, non-polar, acidic and basic. Draw the structure of the amino acid glutamic acid in neutral solution at pH7.0. b) What is meant by the term isoelectric point of an amino acid? Discuss how is it related to the pKa values of an amino acid? c) What practical technique would you use to separate a mixture of the amino acids arginine, valine and glutamic acid? State briefly how it works. d) Describe in detail the two analytical methods that can be used to separate a complex mixture of proteins, yielding individual proteins with different amino acid sequences.

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

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Spectroanalytical Methods

Spectroanalytical methods measure the wavelength and intensity of radiations that are either emitted or absorbed by a molecular or atomic species. These methods are useful for evaluating the electronic or atomic arrangement of the molecules of a given analyte.

Question

1.
a) Classify the amino acids according to the nature of their side chains (R groups),
stating which are polar, non-polar, acidic and basic. Draw the structure of the
amino acid glutamic acid in neutral solution at pH7.0.
b) What is meant by the term isoelectric point of an amino acid? Discuss how is it
related to the pKa values of an amino acid?
c) What practical technique would you use to separate a mixture of the amino
acids arginine, valine and glutamic acid? State briefly how it works.
d) Describe in detail the two analytical methods that can be used to separate a
complex mixture of proteins, yielding individual proteins with different amino acid
sequences.
Many thanks.

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