19. Draw the formulas of prevailing forms of amino acids at given pH values: General procedure of solving such problems Draw maximally protonated form of amino acid. Assign the pKA values to all acidic groups. In each acidic group separately (!), decide whether it is, at the pH given, dissociated or not. If pH < pKA = the corresponding acidic group is predominantly protonated. If pH > pKA = the corresponding acidic group is predominantly deprotonated (dissociated). If pH = pKA = the corresponding acidic group is dissociated exactly from 50 %. a. alanine at pH a) 1 b) 6 c) 11 (PKAI = 2.4; PKA2 = 9.9).

19. Draw the formulas of prevailing forms of amino acids at given pH values: General procedure of solving such problems Draw maximally protonated form of amino acid. Assign the pKA values to all acidic groups. In each acidic group separately (!), decide whether it is, at the pH given, dissociated or not. If pH < pKA = the corresponding acidic group is predominantly protonated. If pH > pKA = the corresponding acidic group is predominantly deprotonated (dissociated). If pH = pKA = the corresponding acidic group is dissociated exactly from 50 %. a. alanine at pH a) 1 b) 6 c) 11 (PKAI = 2.4; PKA2 = 9.9).

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

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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