by STEM Scouts
Are all bubbles round? We’re sure you’re saying, “Of course, because bubbles get their shape by using the least amount of surface area possible to trap the air inside!” Well, you would be correct, but not when it comes to this cubed bubble.
- Large bucket, bowl, or storage container
- Straws (7 pieces)
- Pipe Cleaners (6 pieces)
- Dish Soap
- Glycerin (Optional)
- Begin by gathering six straws and six pipe cleaners. Cut all six of each in half using scissors.
- Run the halved pipe cleaners through the halved straws.
- Using the ends of the pipe cleaners, tie three pieces together. To give you an idea of the shape this should take, when you stand the three tied pieces together up it should create a tetrahedron.
- Create three of these three-piece sections.
- Once you have all three sections made, begin twisting the remaining ends of the pipe cleaners together. This time, you’re only tying one end to another. Remember: The goal is to make a cube!
- After you’ve finished making your cube, set it to the side. It’s time to start making your bubble mixture. The ideal ratio for the solution here is 1:6—that’s one part dish soap to six parts water. We made a few gallons so we could completely submerge the cube. We made a few gallons of the mixture, but you can start off with 1 cup dish soap and 6 cups of water and increase the amounts depending on the size of your container. When adding the soap, slowly stir it in until it has completely mixed.
- To create a stronger more malleable bubble you can use glycerin or light corn syrup. This is optional but encouraged! Note: We did not use either of these in our solution and still had success. For each 1:6 cup mixture, use 1 tablespoon of glycerin or 1/4 cup light corn syrup.
- Now that your cube has been made and your solution prepared, it’s time to experiment! Dip your cube into the mixture, ensuring the solution has taken on all six sides of the cube. Shake the cube to try and get the sides to touch. See what different shapes it can take.
- When all of the sides are touching, wet your extra straw in the solution and stick it into the center. Now gently blow into it. A cubed bubble should be forming in the center. You can pull the straw out or try withdrawing the air through the straw.
How Does It Work?
Steve Spangler Science explains:
“Bubbles form because of water’s reduced surface tension in the presence of soap. Hydrogen atoms in a water molecule are attracted to oxygen atoms in other water molecules. They like each and they want to cling together. Soap molecules help them be more ‘stretchy’ by butting in and decreasing the force of attraction. Soap (and glycerin) also reduces evaporation of water molecules so bubbles can last longer. Why are bubbles round? Physicists will tell you that bubbles use a minimum amount of surface area to enclose the volume of air trapped inside. In this activity, however, as you dip the Square Bubble Maker into the solution, the solution is stretched between the struts and the soap films cling to the sides of the structure, causing the bubbles to appear square or cubic. The soap film uses the shortest distance possible while still connecting all sides. Notice, however, that even the bubble you added at the end bulges slightly on its sides. Bubbles love a spherical shape!”