Key Stage 3
Meaning
Identifying Pure Substances is a set of methods that can be used to determine if a substance is a mixture of other substances or whether it is pure.
About Identifying Pure Substances
- To identify if a substance is pure the experimenter should try several separation techniques.
To find if a liquid is pure:
- 1. Filter the substance. If a residue is left in the filter paper, then the substance is not pure.
- 2. Distill the substance. If a material is left behind during distillation then it is not pure.
To find if a solid is pure:
- 1. Dissolve the solid in a solvent.
- 2. Place a drop of the solution on chromatograph paper and use the same solvent to complete a chromatography experiment. If two or more separate patches appear, then it is not pure.