- an adult helper!
- a clear plastic 2-litre bottle
- Pour 2 inches of warm tap water into the bottle.
- Light a match and let it burn for 2 seconds before blowing it out.
- Let as much smoke as possible drift into the bottle before putting the cap on tightly.
- Shake the bottle for one minute.
- Squeeze the bottle hard for a few seconds, then release your squeeze. Do it again until a cloud forms.
When do you see the cloud appear?