This fun and easy experiment is a great one to do at home. In fact, you probably already have everything you need!

What you need:

  • Empty jar with a lid
  • Hot water
  • Ice
  • Hair spray


First, add about 1/3 cup of hot water to your jar. Swirl the jar around to coat the sides.

Turn the lid to your jar upside down so it can hold some ice, and then place it on top of your jar for about 20 seconds.

You’ll start to see a cloud forming at this point. To make the cloud more visible… quickly remove the lid, add some hairspray and then replace the lid.

Watch as the cloud becomes thicker in the jar! When you’re ready, remove the lid and ice and watch your cloud float out!

How does this work?! Hot water is key in this experiment. The hotter the water is, the more water will evaporate up into the jar. That water vapor makes its way up toward the lid coming in contact with the ice, cooling it down. This causes some of that water vapor to condense turning back into water. To get more water vapor to condense in your jar you add small particles… In nature, water vapor will condense onto things like air pollution or dust… with this experiment, it condenses to the hairspray.

And that’s how you get a cloud in a jar!