Chromatography
Chemistry: AQA GCSE Higher, topic 8.1.3
Chromatography
Chromatography is a process that separates a mixture into its different components.
The 2 phases in chromatography
- Substances are picked up and carried by a mobile phase (liquid or gas).
- The mobile phase then moves through a stationary phase (solid or viscous liquid).
Separation of substances
- This depends on the distribution of a substance across the 2 phases:
- A substance moves far if it's more attracted to the mobile phase.
- A substance doesn't move far if it's more attracted to the stationary phase.
Strength of attraction
- Different components can sometimes be equally attracted to a solvent.
- So, the number of spots a mixture produces can vary depending on the solvent used.
Test yourself on Chromatography
A substance in a mixture is much more strongly attracted to the stationary phase than the mobile phase during chromatography. How far would this substance travel up the paper?
Which state of matter can a mobile phase in chromatography not be?
Which of the following happens in chromatography?
Stages of Chromatography
What does chromatography do to a mixture of substances?