The r group is unique to each amino acid therefore

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Unformatted text preview: all amino acids except glycine (when R = H); the L- amino acids occur naturally and all, except cysteine, are S stereoisomers. Because each amino acid contains both acid and base moieties, it is possible to determine the pKa values for each acidic proton from a titration curve. The pKas for all of the carboxylic acid groups are near 2 and the pKas of all of the amino groups are near 9. The R group is unique to each amino acid, therefore its chemical properties are most often the ones used for identification purposes. This goal of this exercise is to utilize titration curves to identify unknown amino acids. Amino acids that contain an acidic or basic R group will have three Figure 2: Formation of a peptide titratable protons; the carboxylic acid proton, the amino proton, and bond. the R group proton. We should expect to observe all three equivalence points. However, as you may recall f...
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This lab report was uploaded on 04/06/2014 for the course CHEM 272 taught by Professor Dr.brooks during the Summer '08 term at Maryland.

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