Springtime is the perfect time to go outside and blow some bubbles. And with a basic understanding of science, you can have incredible fun while upping your bubble game.
First, let’s get started by making our own bubbles.
Bubble solution materials
Water
Dawn dish soap
Glycerin
A container for mixing and storing bubble solution
To make the bubbles, start by adding water to the container, then add dish soap and a squirt of glycerin. If possible, let the solution sit for 24 hours before using it. Watch along in the video above as we make ours. Note: Bubble solution can be made without glycerin, but it will add strength to your bubbles.
Now let’s have some fun with our bubbles. First, let’s try to bounce them. Once you have your bubble solution, all you need is a bubble wand or pipet and a glove.
First, blow a bubble with a wand or pipet and try to catch it. What happens? It pops. Now put on the glove and try to catch it. What happens? You can hold it or bounce it!
How does this work? Experience has shown us that bubbles usually burst when they come into contact with just about anything. Why do bubbles pop? A bubble’s worst enemies are oil, dirt and gravity. A “super” bouncing bubble will bounce off of a surface if that surface is free of oil or dirt particles that would normally cause a break in the thin soap film of the bubble. The problem with gravity and evaporation is that the water film gets very thin (down to a millionth of an inch) on the top surface as time passes. It finally gets too thin to hold onto itself and the wall collapses completely.
For more bubble fun, let’s try to make square bubbles. To do this, you’ll need to make a cube out of six pipe cleaners cut in half and six straws cut in half. Watch the video above to see how to construct your cube.
Once you have your cube, you’ll need a large container of bubble solution so you can fit your cube in the solution. Once the cube is in the bubble mixture, let it sit for a few seconds. Then lift it out by holding two corners. Giving the cube a gentle shake helps the soap film even out itself and causes excess solution to drip back into the container. Set the “square” bubble on a flat surface to keep the bubble film stable.
You can gently shake the cube to change which way the film faces or just rotate the cube to make sure the square bubble in the center is horizontal. You need to see the square when you look down into the cube from above it.
Now use your bubble wand or a pipet to blow a bubble and drop it into the center of the square. Voilá! The bubble you dropped into the cube “magically” transforms from a sphere to a bulging cube. Now that’s a square bubble!
How does this work? Bubbles form because water has reduced surface tension in the presence of soap. Hydrogen atoms in one water molecule are attracted to oxygen atoms in another water molecule. (This is an example of cohesion). They like each other and they cling together. Soap molecules help them be more “stretchy” or flexible by butting in and decreasing the force of the attraction. Soap (and the glycerin) also reduces evaporation of water molecules so individual bubbles can last longer. There is also some strengthening of the soap film.
Why are bubbles always round? Physicists will tell you that bubbles use a minimum amount of surface area needed to enclose the volume of air trapped inside. In this activity, however, as you dip the cube into the bubble solution, the solution stretches between the edges and the soap film clings to the sides of the cube. (This is an example of adhesion). This causes the bubbles to appear square or cubic. The soap film connects the shortest possible distance while still connecting all sides. Notice, however, that even the bubble you blew into the center at the end bulges slightly on its sides. Bubbles love a spherical shape!
Now that you’ve learned all about bubbles, go outside and experiment! How many bounces can you get with your bubbles? Now that you know about some of bubbles’ properties, can you get bubbles inside of bubbles? Can you shake hands through a bubble? What type of shapes can you get? Start noticing all the shapes around you. Are there other things in nature that tend toward spherical shapes?
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