That cloud you made? It's not a trick. It's exactly how real clouds form. You just did it in a bottle.

The warm water fills the bottle with invisible water vapour — tiny water molecules floating in the air. They want to turn back into droplets, but they can't do it alone. They need something to grab onto. That's where the smoke comes in. 

Those tiny smoke particles become condensation nuclei — little landing pads for water molecules to cling to.

But here's the trigger. When you release the bottle, the pressure drops in an instant — and when pressure drops, so does temperature. 

Suddenly, it's cold enough for those water molecules to cluster around the smoke particles and — cloud.

Squeeze again and watch it vanish. The pressure rises, the temperature climbs, and the droplets evaporate right back into invisible vapour.

Did you notice the cloud only appears when you release — never when you squeeze? And did you notice how quickly it disappears? That's not the cloud going anywhere — that's the same water, just switching form in a split second.

Real clouds do exactly this — just much, much higher up.

But here's the question —  Find out more in The Crazy Scientist Lab!