Science: Investigating Bubbles: Surface Tension and Shapes
Explore how bubbles form, stretch, and become round
Science: Investigating Bubbles: Surface Tension and Shapes
Explore how bubbles form, stretch, and become round
Science - Grade 2-3
- 1
A bubble is made from soap, water, and air. What is inside a bubble?
Think about what fills a balloon.
Air is inside a bubble. The soap and water make a thin film around the air. - 2
Surface tension helps the surface of water act a little like a stretchy skin. How does soap help when you blow bubbles?
Soap helps the water stretch into a thin film. This makes it easier for a bubble to form and last longer. - 3
When a bubble floats in the air, it usually looks round like a sphere. Explain why a bubble is usually round.
Think about the bubble film pulling gently from every side.
A bubble is usually round because the soap film pulls evenly in all directions. A round shape uses the least surface for the air inside. - 4
Mia blows a bubble through a square bubble wand. What shape will the bubble most likely be after it leaves the wand?
The wand shape can start the bubble, but the bubble changes shape as it floats away.
The bubble will most likely become round. Even if the wand is square, the bubble film pulls into a sphere after it leaves the wand. - 5
You touch a bubble with a dry finger, and it pops. Why might the bubble pop?
The dry finger can break the thin soap film. When the film breaks, the air escapes and the bubble pops. - 6
A student touches a bubble with a finger dipped in bubble solution. The bubble does not pop right away. Why might the wet finger help?
A finger covered with the same solution is gentler on the bubble film.
The wet finger has bubble solution on it, so it is less likely to break the soap film. The bubble can stretch around the wet finger for a short time. - 7
Look at these observations: Bubble A lasted 2 seconds. Bubble B lasted 8 seconds. Bubble C lasted 5 seconds. Which bubble lasted the longest?
Bubble B lasted the longest because it stayed for 8 seconds, which is more than 2 seconds or 5 seconds. - 8
In an investigation, one group blows bubbles inside near a fan. Another group blows bubbles inside with no fan. Which setup is more likely to let bubbles last longer, and why?
Think about what wind does to a light bubble.
The setup with no fan is more likely to let bubbles last longer. Moving air from the fan can push and break the bubbles faster. - 9
Draw or describe what happens when two bubbles touch each other gently. What shape can you see where they meet?
When two bubbles touch, they can share a flat wall between them. The outside parts of the bubbles still look curved. - 10
Why is it important to keep only one thing different during a bubble experiment, such as changing only the amount of soap?
A fair test helps you know what caused the result.
It is important to change only one thing so the test is fair. Then you can tell if the amount of soap caused the bubbles to change.