EXPERIMENT: The Perfect Bubble Procedure 1. 2. 3. 4. 5. 6. 7. 8. Work in small groups to develop a ratio for the prefect bubble mixture. Record your prediction in the chart Make your bubble mix. Test your bubble mix Make modifications based on the performance of you mix compared to other student groups. Record what you changed. Test the modified concoction Record your results. Hypothesis: What ratio of ingredients will make the best bubble solution? Remember not to add the unit just the ratio. Data: Ingredient Glycerin Dawn Soap Water Hypothesis Modification Best Recipe in Class Observations: How well did your original recipe work? Make notes about how long the bubbles lasted, how strong they were and how big they could be. Compare how long the bubbles lasted, how big the bubbles got, and how strong they were (how passable they were) to other student groups’ recipes. EXPERIMENT: Dry Ice Bubble 1. Fill your graduated cylinder half-full with warm water. 2. NOTE: Before handling any dry ice, put on a pair of heavy gloves. Dry ice is so cold (-110ºF/-78ºC) that it will burn your skin! Make sure that you have pieces of dry ice that are small enough to fit inside your graduated cylinder. If not, put on a pair of safety glasses and use a hammer to break the dry ice into smaller pieces. 3. Once you’ve created the small pieces, drop a few into the graduated cylinder. Once in the water, the dry ice will begin to bubble and produce a smoke within the cylinder. Eventually the smoke flows right over the top. 4. Put a squirt of dish soap into the cylinder and watch what happens! Before you know it, a column of bubbles begins to form at the mouth of your cylinder. 5. Grab those bubbles and give them a squeeze! These bubbles burst with an amazing explosion of fog. HOW DOES IT WORK When you add dry ice to warm water, you immediately see the dry ice begin to bubble and create fog within the container. This “smoking” effect is directly caused by the rapid warming of the dry ice. Dry ice is frozen, compressed carbon dioxide gas and when you add it to warm water, it combines with the water to create the fog (carbon dioxide and water vapor) that you see bubbling out of your cylinder. Adding soap to burping, bubbling, smoking water creates a whole new effect. Instead of the dry ice just bubbling in the water to make a cloud, the soap in the water traps the carbon dioxide and water vapor in a soapy bubble. Bursting the bubbles in your hands (or as they flow out of the cylinder) releases the gases in a brilliant cascade of fog. EXPERIMENT: Making Bubble Prints What Happens When Bubbles Meet? When bubbles stack, do they remain spheres? No, when two bubbles meet, they will merge walls to minimize their surface area. If bubbles that are the same size meet, then the wall that separates them will be flat. If bubbles that are different sizes meet, then the smaller bubble will bulge into the large bubble. Bubbles meet to form walls at an angle of 120°. If enough bubbles meet, the cells will form hexagons. You can see observe this structure by making prints of bubbles or by blowing bubbles between two clear plates. 1. 2. 3. 4. 5. 6. 7. 8. 9. In a cup or bowl, add two tablespoons of one color of paint. Add one tablespoon of water. Add two tablespoons of dish soap Mix the solution Put the straw or Pipette (with the end cut off) into the mixture and blow bubbles until the cup overflows. Carefully lay the paper on top of the bubbles to make the prints. Or blow bubbles directly onto the paper and watch them pop. Repeat for different layers of color Let dry How Does It Work? Bubble Colors – Similar to the way we perceive the colors in a rainbow or an oil slick, we see the colors in a bubble through the reflection and the refraction of light waves off the inner and outer surfaces of the bubble wall. You can't color a bubble since its wall is only a few millionths of an inch thick. A bubble reflects color from its surroundings. The water in the bubble holds the paint and transfers it to the paper. The bubbles remain clear. Information: How Do Bubbles Clean? Detergents and soaps are used for cleaning because pure water can't remove oily, organic soiling. Soap cleans by acting as an emulsifier. Basically, soap allows oil and water to mix so that oily grime can be removed during rinsing. Detergents were developed in response to the shortage of the animal and vegetable fats used to make soap during World War I and World War II. Detergents are primarily surfactants, which could be produced easily from petrochemicals. Surfactants lower the surface tension of water, essentially making it 'wetter' so that it is less likely to stick to itself and more likely to interact with oil and grease. Modern detergents contain more than surfactants. Cleaning products may also contain enzymes to degrade protein-based stains, bleaches to de-color stains and add power to cleaning agents, and blue dyes to counter yellowing. Like soaps, detergents have hydrophobic or water-hating molecular chains and hydrophilic or water-loving components. The hydrophobic hydrocarbons are repelled by water, but are attracted to oil and grease. The hydrophilic end of the same molecule means that one end of the molecule will be attracted to water, while the other side is binding to oil. Neither detergents nor soap accomplish anything except binding to the soil until some mechanical energy or agitation is added into the equation. Swishing the soapy water around allows the soap or detergent to pull the grime away from clothes or dishes and into the larger pool of rinse water. Rinsing washes the detergent and soil away. Warm or hot water melts fats and oils so that it is easier for the soap or detergent to dissolve the soil and pull it away into the rinse water. Detergents are similar to soap, but they are less likely to form films (soap scum) and are not as affected by the presence of minerals in water (hard water). Draw an image that shows the relationship of soap, water, and oil molecules. Label the image with the hydrophilic and hydrophobic parts of the molecules and the polarity to show how each are attracted or repelled by each other. EXPERIMENT: Bouncing Bubbles 1. 2. 3. 4. Pour 3 parts water and 1 part dish soap into a small cup. Stir to combine. Test your solution with your bubble wand. Try holding a bubble in your hand. Put on the glove. Now, blow a bubble. Try holding the bubble and bouncing it. HOW DOES IT WORK A bouncing bubble is amazing because most people have never seen a bubble bounce, much less be the person who actually does the bouncing! Experience shows that bubbles usually burst when they come in contact with just about anything. Why? A bubble’s worst enemies are oil, dirt, and gravity. A “super” bubble will bounce off of a surface if the 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. Similar to the way we perceive the colors in a rainbow or an oil slick, we see the colors in a bubble through the reflection and the refraction of light waves off the inner and outer surfaces of the bubble wall. You can’t color a bubble since its wall is only a few millionths of an inch thick. A bubble reflects color from its surroundings. EXPERIMENT: Square Bubbles 1. Build a cube using the blue struts and white balls. Place the end of the blue struts into the openings in the balls to build a square. Once you have built two squares, use four more struts to connect the squares so that you have a complete cube. 2. Cut off the rounded tip of the of the pipette to create a bubble blower. Cut off just a little bit so that the pipette is now open at both ends. 3. Add enough water to a large container so the cube can be completely submerged. Add some Square Bubble Concentrate to the water until you have created the perfect bubble solution. It may take a few tries to get the mixture just right, so keep adding concentrate if needed. Make sure to mix the final solution completely. 4. Test your bubble solution by using the pipette to blow a bubble. Make sure you are able to blow a large bubble without it popping. 5. While holding onto the corners of the cube, completely submerge it in the bubble solution. It is very important that the water is deep enough to completely cover the cube. Add water if needed. 6. Slowly pull the cube out of the water making sure there is a flat, square bubble in the center of the cube. You can gently shake the cube to change which way the square faces or just rotate the bubbleized cube. Make sure the square bubble in the center is horizontal and you can see the shape when you look down into the cube from above it. 7. Hold the corner of the cube with one hand, or set the cube on a flat surface. Use the pipette to blow a bubble and carefully drop it into the center of the cube from the top . This may not work on the first try, but don’t let that get you down. When the bubble hits the center square, it changes from a sphere to a bulging cube. You now have what you thought would be impossible: a really square bubble. HOW DOES IT WORK In this activity, as you dip the Square Bubble Maker into the solution, the solution is stretched between the struts and the soap film clings 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!