| Equation for Rf value | distance travelled by substance/ distance travelled by solvent |
| What is chromatography | Analytic technique used to separate different substances from mixtures |
| Paper chromatography experiment | 1) Take filter paper and draw a line near the bottom(baseline)
2) Add a sample of ink to the pencil line
3) Add a shallow amount of solvent to the beaker
4) Then place filter paper into solvent but make sure it doesn't submerge the pencil line
5) Wait for the solvent to seep up the paper, then the different dies which make up ink will dissolve and rise with it
6) Take out the paper and leave it to dry |
| How does each die travel | At different rates - each one must be a different substance |
| What is the mobile phase | substances the molecules can move in e.g. liquid or gas |
| What is the stationary phase | Substance the molecules cant move in e.g. viscous liquid or solid |
| Chemicals more soluble in solvent | Spend more time in mobile phase therefore moving faster |
| Chemicals less soluble | spend more time in stationary phase therefore moving more slowly |
| What is a reference substance | A pure sample that runs alongside the unknown mixture to see if its a component in the mixture |
