WHAT YOU NEED.

• An empty plastic bottle like this one (2 Litre), with the lid
• A jug of warm water
• A match

Instructions:
1. Fill the plastic bottle on third full with warm water.
2. Put the cap on and squeeze, then release, the bottle. Nothing happens.
3. With adult supervision… light a match and place it into the bottle, replacing the lid very quickly… like this.
4. Try squeezing and releasing the bottle again… see what happens?

A cloud appears in the bottle.

So what is happening?
Well, to make a cloud you need water vapour… provided here by our warm water, you need small particles, like the smoke from the match and you need a decrease in pressure…which is why we squeeze, then release, the bottle.

Try it again… just squeeze and release and the cloud appears again.