Which of the following statements best describes your observations? Larger inner column diameters require higher flow rates and larger volumes of mobile phase to reach a good velocity, therefore the 4.6 mm column is better equipped at managing an increase of injection volume, whereas the 2.3 mm column becomes overloaded, and resolution suffers Increasing the injection volume overloads both columns, equally, therefore the resolution becomes worse, equally, for both columns Larger inner column diameters result in a decrease of the terms in the van Deemter equation; therefore the 4.6 mm column has less band broadening, and its resolution is better than the 2.3 mm column Smaller inner column diameters have less longitudinal diffusion, therefore increasing the injection volume has a worse impact on the resolution of the 4.6 mm column

Which of the following statements best describes your observations? Larger inner column diameters require higher flow rates and larger volumes of mobile phase to reach a good velocity, therefore the 4.6 mm column is better equipped at managing an increase of injection volume, whereas the 2.3 mm column becomes overloaded, and resolution suffers Increasing the injection volume overloads both columns, equally, therefore the resolution becomes worse, equally, for both columns Larger inner column diameters result in a decrease of the terms in the van Deemter equation; therefore the 4.6 mm column has less band broadening, and its resolution is better than the 2.3 mm column Smaller inner column diameters have less longitudinal diffusion, therefore increasing the injection volume has a worse impact on the resolution of the 4.6 mm column

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter28: High-performance Liquid Chromatography

Section: Chapter Questions

Problem 28.23QAP

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The following data are for a liquid chromatographic column: Length of Packing 24.7 cm Flow rate 0.313 mL/min Vm 1.37 ml Vs 0.164 ml A chromatogram of a mixture of species A, B, C, and D provided the following data: 1. Width of Peak Base Retention Time, min (W), min Nonretained 3.1 A 5.4 0.41 13.3 1.07 C 14.1 1.16 D 21.6 1.72 Calculate the retention factor.