Question

Multiparty question

Gc= gas chromatography lab

Briefly explain the various parts of a GC - Injection port, oven, copper coil, and detector.,

Then Identify the stationary phase and the mobile phase. And finally What is the problem with setting the oven temperature too high when programming the parameters? What is the problem with setting it too low?

Answer 1

Answer:

Injection port:

Injectors are used to provide constant volume injection of sample into the carrier gas stream. Inertness and reproducibility of injection are essential to maintain high level of accuracy. The injectors should be able to handle small volumes of the order of microliters with highest precision.

Oven:

The Oven can maintain the constant tenperatures or can maintaine the various temperatures for the Analysis (temperature programming)

The set temperature or the temperature variation should be precise and repeatable to ensure reproducibility of separation as minor temperature changes lead to changes of retention time of eluted components.

Copper coil:

It can be seen in the Oven and can gives the temperature for the Oven.

Detector:

Detector can gine the specific response for the separated components of the mixture.

Majority of the organic compound applications require flame ionization detector and for specific requirements detectors.

mobile phase:

Gas Chromatography uses a gas as carrier mobile phase. It is specially suited for compounds that are volatile, thermally stable and have low molecular weights.

The Analysed sample can be Injected and it can be vapourised then it enters in to column along with the carrier gas.

Temperature:

In the high temperature conditions the mixture may not be separated. It may come sa the single peak. In the lower temperatures the high boiling point compounds may not be detected.