A student researcher performed a chromatographic separation of caffeine and aspartame with methanol as the mobile phase using a C,, column. The retention times for methanol (tM), caffeine (tc), and aspartame (tA) were 27.9 s, 95.0 s, and 163.4 s, respectively. What is the separation factor (relative retention), a, for this column? a = Calculate the hypothetical retention times for caffeine and aspartame if their retention factors were reduced by 27.0%. Assume the mobile phase retention time (tM = 27.9 s) remains constant. tc = tA = Select the statements that correctly describe the outcome if the distribution constant for caffeine (Kp) were to decrease.

A student researcher performed a chromatographic separation of caffeine and aspartame with methanol as the mobile phase using a C,, column. The retention times for methanol (tM), caffeine (tc), and aspartame (tA) were 27.9 s, 95.0 s, and 163.4 s, respectively. What is the separation factor (relative retention), a, for this column? a = Calculate the hypothetical retention times for caffeine and aspartame if their retention factors were reduced by 27.0%. Assume the mobile phase retention time (tM = 27.9 s) remains constant. tc = tA = Select the statements that correctly describe the outcome if the distribution constant for caffeine (Kp) were to decrease.

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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