Question

What effect would each of the following have on the retention times in a gas chromatography?

a) increasing the column temperature

b) increasing the flow rate of the carrier gas

c) increasing the amount of sample injected

Answer 1

a) As the temperature increases the retention time get shorter but it's also result in poor seperation because some component stay in gas phase.

b) A high flow rate reduces retention time but poor seperation would be observed. Because the component have very little time to interact with the stationary phase and are just being push through the column.

c) Increases the amount of injected sample change the peak or you can say the chromatogram it has nothing to do with retention time .

Hence , increasing the temperature and flow rate of carrier gas decreases the retention time.