Have you ever wondered why some things fizz, bubble, foam, or change shapes or colors when you mix them together? Here you will learn the science behind some very cool reactions – and you can even try them out at home (start with this Basic Chemistry Set)!
Well, your balloon might not quite fly away in this experiment, but you can make it inflate by creating a reaction in a bottle.
1. Stretch the balloon out by blowing it up and releasing the air three times.
2. Pour the warm water into the bottle. Make a funnel by rolling a piece of paper into a cone shape, then put the pointed end into the mouth of the bottle. Pour the sugar into the bottle through your funnel. Put the cap on and shake the bottle until most of the sugar has dissolved. Take the cap off.
3. Put your funnel in the mouth of the bottle and pour the yeast in so that it floats on top of the sugar water.
4. Quickly attach the balloon to the mouth of the bottle.
5. Set the bottle in a place where it won’t be disturbed and write in your notebook what time it is.
6. Go back and check the bottle after two minutes and write down changes you see to the liquid in the bottle or to the balloon.
7. Check it again in five minutes and write down any changes. If it doesn’t look like much is happening, leave it for about 15 minutes and then look at it again.
8. Continue to check on the bottle and balloon about every 15 minutes. The reaction may continue for up to several hours. Watch closely and write down any changes you notice!
Now that you know how it works, you might want to try the experiment with other types of sugar mixtures. What do you think would happen if you used your favorite soda or juice instead of the sugar water?
So, if yeast and sugar react this way in a bottle, what happens when you bake with them? Well, the same thing happens, it just looks a little different. Bread and many other baked goods are made from yeast. The yeast reacts with the sugar in the dough and releases carbon dioxide, which creates tiny air bubbles that pop and leave air pockets as the dough bakes into bread. You can get a closer look at the air pockets left behind in a slice of bread.
1. Measure 1 cup of water into the small bowl or cup and add the Borax powder. Stir it well and set it aside. You just made a solution of Borax.
2. Rinse your stirring spoon to get all of the Borax solution off of it.
3. In the larger bowl, measure 1/2 a cup of water and 1/2 a cup of white glue. Stir it well until it is all mixed together.
4. If you want colored slime, add 2-3 drops of food coloring to the glue mixture now.
5. Pour the Borax solution that you made in step one into the glue mixture and start stirring. You should see a big clump form in the colored glue right away, just keep stirring though until the clump has picked up as much of the liquid around it as it can.
6. Now comes the fun part – set your spoon aside and pick up the slime with your hands. Keep it over the bowl and knead it like dough, working it between your fingers. As you play with it, the slime will dry off on your hands and will become less slimy and more like putty.
7. Keep your slime in a plastic zip-lock bag in the fridge when you are not playing with it.
There are lots different types of polymers, including plastic, rubber, Jell-O, glue, camera film, materials such as nylon, and even natural fibers from wood and cotton. This polymer has properties of a solid and a liquid at once. Compare your polymer to a solid object – a piece of chocolate. Break the chocolate in half. Try quickly breaking the wad of slime in half. Did you get a clean break similar to the way the chocolate broke? To see how it is also like a liquid, try slowly stretching the blob out between your hands. You can’t do that with a solid piece of chocolate! The polymer is showing its liquid properties when you stretch it slowly. Now set the slime back into the bowl you made it in and watch what happens. It should flatten out to fill the bottom of the bowl, similar to a liquid like pancake batter would do.
There are all sorts of reactions going on around us each day. A chemical reaction is something that happens when two or more substances come into contact with each other. One substance combines with another and creates a whole ew substance that wasn’t there when the reaction started. Different types of reactions can happen depending on the substances that are put together. Sometimes a little of the original ingredients will be left over after the reaction, and sometimes more than one new substance will be formed in the reaction. In Up, Up, and Away! the yeast reacted with the warm sugar-water and produced carbon dioxide, which you could see filling up the balloon.
In the slime experiment above, you learned what a polymer is – a long chain of hundreds or thousands of tiny molecules. The slime you made is an interesting type of polymer that can act like a solid or a liquid depending on how it is handled. There are lots and lots of polymers in our world. Some are natural and some are made by humans, or synthetic. Here are a few examples of polymers:
For more information and project ideas for teaching kids about polymers, check out our Polymer and Slime Experiments page.
Chemical reaction– when two or more substances come into contact and form a new substance.
Carbon Dioxide– a gas that is in the air on earth, but in very small amounts. Plants need it in order to live; they use it to covert sunlight into food. Humans breathe out carbon dioxide when we exhale. In chemistry, it is abbreviated CO2, which means that is has one carbon atom and two oxygen atoms.
Oxygen – a gas that is very abundant on earth and that humans and most animals breathe to stay alive. It does not have any color, smell, or taste.
Polymer– the word “poly” means many, so a polymer is a long chain of molecules that gives a substance the ability to stretch and be very flexible.
Use this worksheet as a fun activity to reinforce the basic chemistry concepts of chemical reactions and polymers. Kids can color the page and then determine whether each picture is a polymer, a reaction, or neither.