The method to identify a compound by the use of GC should be given. Concept introduction: Gas chromatography is efficiently used for the compounds that have high vapor pressures which allow them to pass through a GC column. A gas chromatography does not identify compounds if unknown samples are loaded into the column. GC is one of type of partition chromatography, where the sample that has to be analyzed get adsorbed on the stationary phase. The stationary phase is formed by high boiling nonvolatile liquid, usually a polymer . An inert gas like helium or nitrogen is utilized to form mobile phase. In GC, no interaction of compound with mobile phase occurs, unlike LC and TLC. The inert gas that makes the mobile phase carries the compound down the column when it is in vapor state. The compounds present in the mixture divide themselves between the gas phase and the liquid phase in the column in an equilibrium. The components of gas-liquid chromatography are as follows: High-pressure pure carrier gas source Flow controller Heated injection port Column and column oven Detector Recording device or data station

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Chapter 20, Problem 4Q

Interpretation Introduction

Interpretation:

The method to identify a compound by the use of GC should be given.

Concept introduction:

Gas chromatography is efficiently used for the compounds that have high vapor pressures which allow them to pass through a GC column.

A gas chromatography does not identify compounds if unknown samples are loaded into the column. GC is one of type of partition chromatography, where the sample that has to be analyzed get adsorbed on the stationary phase.

The stationary phase is formed by high boiling nonvolatile liquid, usually a polymer. An inert gas like helium or nitrogen is utilized to form mobile phase. In GC, no interaction of compound with mobile phase occurs, unlike LC and TLC. The inert gas that makes the mobile phase carries the compound down the column when it is in vapor state. The compounds present in the mixture divide themselves between the gas phase and the liquid phase in the column in an equilibrium.

The components of gas-liquid chromatography are as follows:

High-pressure pure carrier gas source
Flow controller
Heated injection port
Column and column oven
Detector
Recording device or data station

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