Blow the Biggest Bubbles

Key concepts

• Chemistry
• Molecules
• Physics
• Chemical solutions

Introduction

Bubbles can be fun to play with outdoors, but does it seem like they just don't last very long? With a little chemistry on your side you can mix up a solution that lets you make some amazingly huge and durable bubbles—ones that like to linger! Experiment with the shape and size of bubbles as you design your own wands, make a colorful bubble snake and try to grow giant bubbles.

Background

A bubble is a thin film of soapy water filled with air. The soapy film is composed of three layers: one layer of water molecules sandwiched between two layers of soap molecules. Millions of these molecules will stick together to form the spherical shape of a bubble. Now you just need to make this ultrastrong bubble solution and start playing!

Materials

• Water
• Dish soap (Original blue Dawn works best.)
• Glycerin (Pure glycerin is different from soap and can be purchased at many pharmacies in the cosmetics section or where cooking supplies are sold.)
• Sugar
• Container with a lid, such as a plastic food storage container
• One-cup measuring cup
• Measuring spoons (teaspoon and tablespoon)
• Two or more pipe cleaners
• Scissors (optional)
• Cotton string (optional)
• Cotton yarn (optional)
• Two dowel rods or sticks (optional)

Preparation

• This activity is best done outside.

Procedure

• Mix one cup of water with two tablespoons of dish soap, one tablespoon of glycerin and one teaspoon of sugar. What role do you think these different ingredients play in making a strong, long-lasting bubble?
• Stir the mixture thoroughly and store for at least an hour in a covered container. When you're ready to use the solution, gently swirl the container in case the ingredients have separated.
• Now it's time to design your own bubble wand! Be creative! Bend a pipe cleaner into a closed shape so that the two ends meet with at least an inch to spare on each end.
• Use a second (or a second and third twisted together) to serve as a handle; twist the ends of your shaped pipe cleaner to the end of your handle pipe cleaner(s). Now you have your basic bubble wand!
• Dip the wand in the container holding the bubble solution for a few seconds and then lift it out and blow on it. What do the bubbles look like coming off of the wand? How long do they last? Are they more difficult to break than bubbles you blow from a store-bought jar?
• Extra: How big can you go? Experiment by making a giant bubble wand: Use cotton yarn to make two braids, one that measures 18 inches long and another that measures 36 inches. Tape one end of the long braid to the end of one dowel and tape the other end to the other dowel. Tape the shorter braid in the same way to the same ends of the dowels. Both braids should form a loop with the shorter braid at the top and the longer braid at the bottom. Dip the wand into the bubble mix and let the yarn soak in plenty of solution. Lift the wand and slowly move it around to create huge bubbles! How long do your big bubbles last?

Observations and results

Adding glycerin and sugar to the solution helps the bubbles last longer. The water in bubbles evaporates quickly, which makes them more fragile. Adding glycerin and sugar slows evaporation, which makes bubbles last longer.

Did you notice that no matter what your wand looks like, a bubble will always take on the shape of a sphere? The sphere shape minimizes the surface area of the bubble, which makes it the easiest shape to form using the least amount of energy. 

Cleanup

After you are finished making bubbles, pour the unused solution down the drain. 

More to explore

The Science behind Bubbles, from Kids Discover

Surface Tension-Soap Bubbles, from The Indianapolis Public Library

Bubble Science, from About Education

Super Bouncy Bubbles, from the Museum of Science and Industry, Chicago