Paper And Gas Chromatography

Question 1

What are the advantages of instrumental methods of chromatography?

Answer 1

> more accurate

> very fast

> very sensitive- can detect even the smallest amounts of substances

Question 2

What is used to carry the substance through the column in gas chromatography?

Answer 2

A gas

Question 3

What is the retention time and how is it represented?

Answer 3

It is the time taken for a substance to pass through the tightly material packed column.

> represented by hight of peak in gas chromatograph

Question 4

Why are the substances separated in a gas chromatography machine?

Answer 4

They travel through the tightly packed column at different speeds so reach the detector at different times.

Question 5

What does the number of peaks show in a gas chromatograph?

Answer 5

The number of substances

Question 6

What does gas chromatography do?

Answer 6

It can separate out a mixture of compounds and help you to identify the substances present

Question 7

Describe a method of paper chromatography for separating a mixture of dyes

Answer 7

Draw a pencil baseline on the chromatography paper

Place a small amount of dye onto the baseline using a pipette

Place the chromatography paper into a beaker of solvent/ water, making sure the baseline does not touch the solvent

Place the lid on the beaker and wait an amount of time

The solvent will seep up the chromatography paper and carry the different components of the dye different distances depending on how soluble they are.

Question 8

What can a mass spectrometer do?

Answer 8

It can identify the molecular mass by looking at the molecular ion peak ( bar to the right)