1. Distillation
D. Crowley, 2007

2. Distillation
Wednesday, April 19, 2017
To know when to use distillation, and to be able to explain how it works

3. Lost At Sea Imagine you were really stuck for water whilst at sea
Sea water is so salty that it dehydrates you quicker than not drinking any water at all (as well as sending you mad)!
If you were stranded on the boat, and it wasn’t likely to rain, how could you change the salt water into drinkable water in order to survive?

4. Evaporation
Evaporation would separate the two (the salt and water), but it would only leave as the salt
The water would be lost as it evaporates away, but this is a good start…

5. Distillation
Distillation can separate a liquid from a solution (water from salty water)
Distillation works by evaporating the liquid from the solution
It is then cooled and condensed into a separate container
The salt does not evaporate, so we have successfully separated the two…

6. Distillation
Demo of distillation

7. Boiling Temperature
It is really important you know the boiling temperature of the liquid you want
The liquid will only be removed once it reaches this boiling point (at which point it can be condensed and collected)
This means different substances can be separated, based on their boiling temperature - this is the science behind distillation

8. Boiling Temperature
E.g. water and ethanol have different boiling points - the ethanol will boil first (78oC), and then the water (100oC) enabling us to separate the two
This is known as fractional distillation

9. Worksheet
Complete the distillation
worksheet…