A cloud is formed when water vapor condenses into water droplets that attach to particles (of dust, pollen, smoke, etc.) in the air. When billions of these water droplets join together, they form a cloud.
As part of our weather unit, we read several books about clouds. Then we decided to get into some hands-on science by making our own clouds in a jar. There are several methods for making a cloud in a jar. In this post I share two methods we tried and I explain how they work.
You’ll find more resources for learning about weather on Weather Unit Study page my Weather Activities Pinterest board.
We tried two methods for making a cloud in a jar. Both methods involve making water vapor and then providing some sort of particle for the water vapor to condense on. In the first method, we used hairspray as the particle source and in the second method we used smoke from a match as the particle source.
The hairspray method formed a denser cloud that was easily visible and quite impressive to view. The match method was super cool because of how quickly the cloud formed and then disappeared as the air pressure in the jar changed.
How to make a cloud in a jar using hairspray
For this method, you will need the following materials:
- A jar with lid
- About 1/3 cup hot water
- Ice
- Hairspray (which I forgot to include in the picture below)
Start by pouring the hot water into the jar. Swirl it around a bit to warm up the sides of the jar.
Turn the lid upside down and place it on the top of the jar. Place several ice cubes onto the lid, and allow it to rest on the top of the jar for about 20 seconds.
Remove the lid, quickly spray a bit of hairspray into the jar, and then replace the lid with the ice still on top. Watch the cloud form.
When you see a good amount of condensation form, remove the lid and watch the “cloud” escape into the air.
How does it work?
When you add the warm water to the jar, some of it turns to water vapor. The water vapor rises to the top of the jar where it comes into contact with cold air, thanks to the ice cubes on top. Water vapor condenses when it cools down. However, a cloud can only form if the water vapor has something to condense on to. In nature, water vapor may condense onto dust particles, air pollution, pollen, volcanic ash, etc. In the case of this activity, the water vapor condensed onto the hairspray.
How to make a cloud in a jar using a match
For this method, you will need the following materials:
- A jar
- A match
- A balloon with the bottom cut off (so you can get the balloon over the mouth of the jar)
- Warm water
- A flashlight
Pour enough warm water into your jar to cover the bottom 1/2″ of the jar.
Light a match, then hold the lit end in the jar for a few seconds to allow smoke to enter the jar. Then remove the match (or you can simply drop it into the jar – the flame will extinguish when the match hits the water).
Quickly cover the opening of the jar with the cut balloon.
With this next step, the goal is to change the air pressure in the jar by gently pushing and releasing the balloon. Be gentle as you do this to ensure that the balloon does not come off the top of the jar.
With your finger, gently push the balloon into the jar a little bit to increase the air pressure in the jar. Then release. As you release, you should notice a cloud instantly form inside the jar. You may want to shine a flashlight at the jar to help you see the cloud more clearly.
You can repeating the pushing and releasing several times and you will see additional clouds form.
How does it work?
When you add the warm water to the jar, some of it turns to water vapor. When you press on the balloon, you increase the air pressure in the jar, which results in warmer air. When you then release the balloon, you decrease the air pressure in the jar, which results in cooler air. As the air cools, the water vapor in the jar condenses. The condensed water vapor is able to collect on the smoke particles from the match, and thus you see a cloud form.
More weather resources
More weather posts from Gift of Curiosity:
- Books about the weather
- Weather 3-part cards
- DIY weather station
- Water cycle demonstration
- Cloud classification activities
- Cloud classification craft
- Make it rain in a jar
- DIY weather vane
- Wind resistance experiment
- Make a tornado in a bottle
- How do hurricanes form?
- Make a hurricane
- Printable weather Bingo game
- Printable weather I Spy game
You’ll find more resources for learning about weather on Weather Unit Study page my Weather Activities Pinterest board.
Follow Katie @ Gift of Curiosity’s board Unit Ideas: Weather on Pinterest.
I think this activities are so interesting for students. I like to practice them in my science class as soon as possible. Thanks for the ideas.
That is such a good idea
Do you use aerosol or pump hair spray – or does it matter?
I used an aerosol spray because that is what I had on hand. I’m not sure how a pump spray would work, although I’m guessing it might not work as well as aerosol. I guess you can always give it a try and see though!
Amazing.Iam going to show the whole expieriment to my pupils in the preschool.It is really iteresting.Thank you,
My greetings from Greece
We just did this and the kids LOVED it! I had 5 kids from the ages of 2-6 and they all thought it was so much fun. My first grader is writing in his science notebook right now about it. Thanks for the easy to follow instructions and great pictures!
I’m glad you found it easy and fun to do. It really is a great activity for kids of all ages!
Did you use a pump hairspray or an aerosol hairspray?
If I recall correctly, we used an aerosol hairspray.
Just did this while waiting for lunch to finish! My kids were super impressed as was the husband. Great quick easy attention getter. Thanks!!!
Thanks for this idea. It looks like a great do it yourself at home project.
I tried the pump hairspray because that’s what I had on hand but I couldn’t get it to work 🙁 Definitely going to try with the aerosol can instead!
I think the aerosol spray will work better. Thank goodness I still had an old can from my high school days!