Normalized Intensity (a. u.) 0.5 1.0 A 3D-printed GC column (shown below) was created for use with "micro" gas chromatography applications. To prove its utility, it was used to separate a mixture of alkanes (C9-C18, C22, C24). For the separation shown below, the column temperature was ramped from 40 °C to 250 °C at a rate of 30 °C per minute. (a) 9 10 = 1 mm 12 13 15 22 0.0 0 100 200 300 400 Time (sec) a) What detector would you use for this analysis? Justify your selection. b) Explain how the chromatogram would change if the separation was run isothermally. c) Explain how the chromatogram would change if the temperature ramp were increased to 50 °C per minute.

Normalized Intensity (a. u.) 0.5 1.0 A 3D-printed GC column (shown below) was created for use with "micro" gas chromatography applications. To prove its utility, it was used to separate a mixture of alkanes (C9-C18, C22, C24). For the separation shown below, the column temperature was ramped from 40 °C to 250 °C at a rate of 30 °C per minute. (a) 9 10 = 1 mm 12 13 15 22 0.0 0 100 200 300 400 Time (sec) a) What detector would you use for this analysis? Justify your selection. b) Explain how the chromatogram would change if the separation was run isothermally. c) Explain how the chromatogram would change if the temperature ramp were increased to 50 °C per minute.

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 28.17QAP: Mass spectrometry is an extremely versatile detection system for GC. However, interfacing an HPLC...

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