Filtration, crystallisation, simple and fractional distillation, and paper chromatography with Rf values.
What you will learn
- Choose a method to separate a mixture
- Explain fractional distillation from boiling points
- Calculate and use Rf values
Pick the method for the job
- Filtration: an insoluble solid from a liquid (sand from water).
- Crystallisation: a soluble solid from its solution: heat to evaporate some water, cool, filter off the crystals, dry them.
- Simple distillation: a liquid from a solution (pure water from sea water).
- Fractional distillation: liquids with different boiling points. The one with the lowest boiling point reaches the top of the column first.
- Paper chromatography: the soluble substances in a mixture, such as the dyes in an ink.
The rest of this lesson and its 8 practice questions are locked.
In this lesson
- Pick the method for the job
- Chromatography and Rf
- Try it: An Rf value
8 practice questions, marked as you go; about 20 minutes in all.
In this unit: Atomic structure and the periodic table
Atoms, formulae and equations, separating mixtures, the model of the atom, isotopes, electrons in shells and the groups of the periodic table.