In column chromatography, the following statements are true except-* The stationary phase is held in a narrow tube through which the mobile phase is forced under pressure The effectiveness of the chromatographic column in separating two solutes depends in part on the relative rates at which the two species are eluted The stationary phase is supported in a flat plate or in interstices where the mobile phase moves through by capillary action or under the influence of gravity Predict the order of elution of the following components if a normal phase column and hexane:methylene chloride mobile phase was used in the separation. (A.) Propanone (B.) Propanoic acid (C.) Methyl ethanoate BCA ABC ACB The following are true for the observed tailings and fronting in a chromatogram, except- Fronting and tailing leads to a good separation and reproducible elution times Tailing is observed when the tail appears to the right of the chromatogram and front is steepened while fronting is observed when the tail is steepened Common cause of fronting and tailing is a distribution constant that varies with concentration

In column chromatography, the following statements are true except-* The stationary phase is held in a narrow tube through which the mobile phase is forced under pressure The effectiveness of the chromatographic column in separating two solutes depends in part on the relative rates at which the two species are eluted The stationary phase is supported in a flat plate or in interstices where the mobile phase moves through by capillary action or under the influence of gravity Predict the order of elution of the following components if a normal phase column and hexane:methylene chloride mobile phase was used in the separation. (A.) Propanone (B.) Propanoic acid (C.) Methyl ethanoate BCA ABC ACB The following are true for the observed tailings and fronting in a chromatogram, except- Fronting and tailing leads to a good separation and reproducible elution times Tailing is observed when the tail appears to the right of the chromatogram and front is steepened while fronting is observed when the tail is steepened Common cause of fronting and tailing is a distribution constant that varies with concentration

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

Chapter33: Automated Methods Of Analysis

Section: Chapter Questions

Problem 33.8QAP

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