Chromatography

Question 1

Column Chromatography

Answer 1

A column is packed with a solid and a solvent moves down the column

Question 2

Gas Chromatography (What conditions needed?)

Answer 2

A column is packed with a solid (silica/alumina) or with a solid coated by a liquid, and a gas is passed through the column under pressure at high temperature.

Question 3

What does separation depend on in chromatography?

Answer 3

On the balance between solubility in the moving phase and retention by the stationary phase.

Question 4

What thing is used to identify the substances from a chromatogram?

Answer 4

Rf values are used to identify different substances.

Question 5

What is measured in gas chromatography

Answer 5

Retention time for liquids to move through

Question 6

Pros of TLC

Answer 6

Fast
Small amounts
TLC plates more robust than paper

Question 7

Advantages of Column Chromatography

Answer 7

Large amounts can be separated

Question 8

Advantages of GC

Answer 8

Very sensitive

Question 9

Uses of GC

Answer 9

Testing athletes for doping

Question 10

How is gas chromatography confirmed?

Answer 10

Mixture is run through mass spectrometer. Fragmentation patters confirm identity

Question 11

What effects gas chromatography retention time?

Answer 11

Less polar substances travel quicker