What child doesn’t LOVE playing with bubbles? They are fun to play with, but they can also serve as a teaching tool for little ones. Next time you blow bubbles with your child, use the opportunity to teach him/her about surface tension with bubbles.
What Is Surface Tension?
The tension of the surface film of a liquid caused by the attraction of the particles in the surface layer by the bulk of the liquid, which tends to minimize surface area.
That’s what the dictionary says, but here’s how you can explain it to kids. Bubbles are bits of air or gas trapped inside a liquid ball. The surface of a bubble is very thin, and bubbles are particularly fragile when a dry object touches them. That’s because soap film tends to stick to the object, which puts a strain on the bubble.
A Drop Of Water: A Book of Science and Wonder
What You Need:
- 8 tablespoons of dish-washing liquid
- 1 quart water
- 1 drinking straw
- A shallow pan
What to Do
- Mix the dish-washing liquid with the water and pour it into the pan. Give your child a straw and tell him to blow through it as he moves it slowly across the surface of the solution. Ask him to notice the size of the bubbles that he makes.
- Next, have your child try to make a very big bubble that covers the surface of the pan. Have him do the following:
- Dip one end of the straw into the solution. Then hold the straw slightly above the surface. Blow into it very gently. He may have to try several times to make a really big bubble.
- When he’s made a bubble, have him touch it gently with a wet finger to see what happens.
- Have him make another big bubble, then touch it with a dry finger. What happens?
- Ask him to look closely at the bubbles he makes. How many colors does he see? Do the colors change?
Surface Tension Video
Here are more ideas of surface tension you can show your kids. There’s LOTS to talk about and experiment with.
