Chromatography
Science: KS3, topic 2.1.19
Chromatography
Chromatography is a process that separates a mixture into its different components. The pattern formed is known as a chromatogram.
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?
How many chromatography spots are produced by pure samples, and why?
Which state of matter can a mobile phase in chromatography not be?
Which of the following happens in chromatography?
Stages of Chromatography