6.3.1 Chromatography and qualitative analysis Flashcards
(5 cards)
1
Q
How to carry out TLC
A
Take a sheet/plate of glass, plastic or metal.
Coat it with a thin layer of silica gel or alumina.
Draw a pencil line near to the bottom.
Place a small drop of the sample on this line.
Place the plate in a beaker containing solvent, but not enough to reach the pencil line.
Cover the beaker.
2
Q
what TLC what is the mobile phase
A
liquid
eg-solvent
3
Q
in TLC what is the stationary phase
A
soild
eg-silica gel/alumina
4
Q
what are 2 factors affecting the movement up the plate
A
- retention by stationary phase
- solubility in solvent
5
Q
what is Rf value
A
Rf value=distance moved by solute/distance moved by solvent
