Why are necessary 9 distinct mobile phases, applied in sequence, in this chromatographic separation? A To promote the elution of all pigment fractions, which span a wide range of polarities (and hence exhibit different strengths of attachment to the Alumina matrix). (B In order to facilitate the progression between the extreme polarities of the mobile phases, while assuring that each of the 9 mobile phase preparations is miscible with its neighboring preparations. There is no special reasoning behind the choice, as the choice was made by trials. D The minimum number of 9 mobile phases is a requirement in classical chromatography.

Why are necessary 9 distinct mobile phases, applied in sequence, in this chromatographic separation? A To promote the elution of all pigment fractions, which span a wide range of polarities (and hence exhibit different strengths of attachment to the Alumina matrix). (B In order to facilitate the progression between the extreme polarities of the mobile phases, while assuring that each of the 9 mobile phase preparations is miscible with its neighboring preparations. There is no special reasoning behind the choice, as the choice was made by trials. D The minimum number of 9 mobile phases is a requirement in classical chromatography.

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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