Rain in a jar
Explore the calming experience of my ‘Rain in a Jar’ experiment. Learn about the water cycle and precipitation in a simple yet fascinating way. Join me as we observe and understand the natural phenomenon of rain right from the comfort of your home or classroom.
What you need:
- Large cup of water
- Small cup of water
- Shaving cream
- Blue food coloring
- Pipette
What to do?
- Mix blue food coloring with a little water
- Pour water into the larger cup
- Add a cloud of shaving cream on top
- Use the pipette to drop blue drops onto the “cloud”
What is happening?
Our shaving cream is mostly air, so the foam is less dense than the water and will float on top of it. The food coloring has a similar density to water, so it will slowly sink through the foam until reaching the water layer. Once it hits the water, it will dissolve and disperse in an effect that looks like a bursting color explosion.
This demonstrates the concept of density. The denser water sinks below the less dense foam. The food coloring, being similar density to water, can pass through the foam but disperses when hitting the water. It allows you to visualize and compare the relative densities of the three substances used.
