Nonpolar aromatic compounds were separated by HPLC on an octadecyl(C18) bonded phase. The mobile phase was 65 vol% methanol in water. How would the retention times of these aromatic compounds be affected if 90 vol% methanol was used instead? The retention times will be longer in 90 vol% methanol. The retention times will double. The retention times will not change. The retention times will be shorter in 90 vol% methanol.

Nonpolar aromatic compounds were separated by HPLC on an octadecyl(C18) bonded phase. The mobile phase was 65 vol% methanol in water. How would the retention times of these aromatic compounds be affected if 90 vol% methanol was used instead? The retention times will be longer in 90 vol% methanol. The retention times will double. The retention times will not change. The retention times will be shorter in 90 vol% methanol.

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

Chapter27: Gas Chromatography

Section: Chapter Questions

Problem 27.24QAP

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