Outcomes

Pupils should understand that in order to form vapor, the molecules of the liquid must overcome the forces of attraction between them.
Pupils should know that the temperature of a boiling liquid remains constant, even when more heat is added.
Pupils should understand the process of Evaporation and how it is used for cooling in a range of applications

Specification References

5.10 Understand that a substance can change state from liquid to gas by the process of evaporation or boiling.

Using a cotton wool swab, place a drop of ethanol on the back of one hand and a drop of water on the other and discuss the feeling and the causes of it.

Pupils are given a range of water samples and are asked to determine which sample is ‘contaminated’
Find the boiling point of water samples (one distilled water/ other will salt added)

Pupils watch a demonstration of the forced evaporation of ether that causes water to freeze; a discussion should follow

Bunsen burner kit, beakers, thermometers, samples of distilled and contaminated (salt) water

Pupils should be asked whether they have dry skin or cuts before applying Ethanol as it may sting. For more information see the risk assessment: The use of ethanol
Teacher and Pupils should wear goggles as a chemical is being used.
Ethanol should be put out of harms way before the main experiment involving bunsen burners starts.
Pupils should not sit down whilst heating the different solutions during this experiment.
Pupils must wear goggles and have their hair tied back and ties tucked away.
Pupils should be told what to do if they get burnt.