Chromatography

Question 1

What is chromatography used for?

Answer 1

To separate a mixture of soluble solids/solutes

Question 2

Why mustn’t the spot of ink be placed in the water?

Answer 2

If the solvent was above the baseline, the ink being tested would dissolve into the solvent and not move up the paper

Question 3

Why should the baseline be drawn in pencil and not pen?

Answer 3

Ink in the line would mix with the ink being tested and move up the paper

Question 4

Why would it be preferable to carryout chromatography in a sealed container (with a cover/lid)

Answer 4

Using a lid would stop the solvent from escaping or evaporating

Question 5

How can you tell which substance is the most soluble in the solvent?

Answer 5

The substance which has moved furthest up the chromatography paper is the most soluble in the solvent.

Question 6

If the dot does not move from the baseline, what can you infer?

Answer 6

The ink is insoluble in the solvent

Question 7

Rf

Answer 7

Distance solute has travelled / Distance solvent has travelled

Question 8

How to measure the distance the solute has travelled

Answer 8

Measure from the base line to the centre of the dot of solute

Question 9

How to measure the distance the solvent has travelled

Answer 9

Measure the distance between the base line and the solvent front