Q. Mobile phase can play a key role in the separation of weak acids and weak bases. The separation of the compounds below was carried out on a silica based reverse phase C18 column. a) Using the following compounds in the table below as an example, explain in detail how their retention is impacted by changes to the HPLC mobile phase at a PH of 2.8 and 6. Include a sketch of a diagram to illustrate your answer. b) which of the compound below might experience peak tailing at PH 6? With residual silanol groups on the column, explain why this may occur and suggest a potential solution? NH2 Aniline (pKa 4.6) CH3 HO levulinic acid, (pKa 4.7)

Q. Mobile phase can play a key role in the separation of weak acids and weak bases. The separation of the compounds below was carried out on a silica based reverse phase C18 column. a) Using the following compounds in the table below as an example, explain in detail how their retention is impacted by changes to the HPLC mobile phase at a PH of 2.8 and 6. Include a sketch of a diagram to illustrate your answer. b) which of the compound below might experience peak tailing at PH 6? With residual silanol groups on the column, explain why this may occur and suggest a potential solution? NH2 Aniline (pKa 4.6) CH3 HO levulinic acid, (pKa 4.7)

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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