There are a number of ways that you could separate liquids in Chemistry. This is an outline of the required steps to undertake one of these methods.
Discuss why fractional distillation is used to separate this sort of mixture.
Record the results in a suitable table. For example:
|Ink||Spot colour||Distance travelled by spot (mm)|
A student measured the distance moved by a spot to its lowest part instead of to its centre. How does this mistake affect the Rf value calculated for the spot?
It is smaller. The top line of the Rf expression is less, but the bottom line is the same.
It is important in this practical activity to use appropriate apparatus and methods. This includes the safe use and careful handling of substances.
Evaluate the hazards and the precautions needed to reduce the risk of harm. For example:
|Hot apparatus||Skin burns||Allow apparatus to cool before touching it|
|Ethanol||Flammable||Only heat the ethanol-water mixture with an electric heater or in a water bath|
|Broken glass||Cuts||Be careful when placing the fractional distillation apparatus in the clamp and do not overtighten the clamp|
|Harmful solvent||Skin irritation||Avoid skin contact, eg wear gloves|
|Harmful solvent||Breathing difficulties||Ensure adequate ventilation or use a fume cupboard|