Cloud in a Bottle
A cloud suddenly forms.
Teaching & key ideas
What you do: Pressurize bottle, then release pressure quickly.
What students see: A cloud suddenly forms.
Why it works: Rapid expansion cools air so water vapor condenses into droplets.
Question to ask: Where was the cloud before we saw it?
Lesson flow
Predict → demonstrate → observe → briefly explain → ask: Where was the cloud before we saw it?