The UK is in the middle of a heatwave at the moment, which is great, but also means we need a lot of cold drinks to keep the kids cool. This fun experiment is brilliant for cooling drinks quickly and learning at the same time.
How to cool a drink quickly
What you need:
- A metal bowl
- Drink is a glass bottle
- Half fill the bowl with water and ice.
- Place the drink in the ice.
- Add a handful to salt to the water and stir.
- Watch what happens to the bowl and drink.
The Science Bit
The salt lowers the melting temperature of the ice, making the water temperature drop below zero, and so cooling the drink faster.
We also demonstrated this when we made frost.
Can you design an experiment with a control condition? Maybe ice and water with no salt??
Can you record the temperature before and after adding the salt?
Does the temperature drop further if you add more salt?
What happens if you use a plastic bottle? Does it work as well?
If you use a smaller drinks container does it cool faster?
Note: If you use a can be careful when you open it!