Chromatography
Science Practicals: GCSE, topic 2.1.8
Paper Chromatography
In paper chromatography, mixtures of soluble substances are separated. A solvent (mobile phase) is run through the mixture on paper (containing the stationary phase). The substances will then move up the paper at different rates. The most soluble substance will move the furthest up the paper.
Dip the chromatography paper
- Dip the bottom of the chromatography paper into the solvent.
Solvent movement
- The solvent travels up the chromatography paper.
- As the solvent moves, it picks up the substances being tested and carries them up the chromatography paper.
Distance travelled
- The components that travel furthest are highly soluble (dissolve easily) in the solvent. They are also minimally attracted to the chromatography paper.
Test yourself on Chromatography
In paper chromatography, the components that travel furthest are...
A student uses a gas as one of the phases in a chromatography experiment. Which phase must this gas be?
What can we say if the Rf values of a reference and a spot match in all solvents?
Which of the following describe a reference substance?
What does the process of chromatography produce that can be analysed?