Ever wonder why ketchup doesn't flow easily out of the bottle? Now you know it's because the ketchup acts just like the cornstarch-water experiment here. More examples of non-Newtonian fluids are ketchup, blood, paint, and shampoo.
We're going to whip up a batch of non-Newtonian fluid that's going to act like both a solid and a liquid. Here's what you do:
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Corny Slime Fill a large bowl with two cups of cold water. Mix in one cup of cornstarch. The faster you stir, the harder it is to stir. Go s l o w l y . Grab it with your hand - it should form a hard ball that you can't squish. When you relax your grip, the ball should melt and drip between your fingers as if liquid. If this is not what's happening for you, adjust the amounts of cornstarch and water you have in your bowl.
Click here to learn how to expand this activity into Walking on Water.
We can also make a substance very similar to silly putty using these materials:
- liquid starch (use sta-flo, vano, or make your own from cornstarch and water
- white or clear glue
- disposable cups
- popsicle sticks
What's going on? The water-cornstarch mixture is made up of long molecular chains (polymers) that get all tangled up when you scrunch them together (and the slime feels solid). The polymers are so slick that as soon as you release the tension, they slide free (and the slime drips between your fingers). This of spaghetti noodles with butter - they get tangled up, but are still allowed to slide freely. This cornstarch-water substance is both a solid and a liquid. Scientists call this a non-Newtonian fluid.
For a smaller scale version of this experiment, try making a small amount and placing it in an empty water bottle. Notice how it acts like a liquid when you gently roll the bottle, but turns into solid bits when you shake it hard.
For an edible version of this experiment, replace the water with condensed milk. Heat one can of milk with one tablespoon cornstarch over low heat (get adult help with the stove), stirring until the mixture thickens. Remove from heat and allow to cool. (You can add food dye and/or alcohol-free flavorings if you'd like!) For chocolate slime, add two tablespoons chocolate syrup to the saucepan while cooking... great for a Slime Birthday Party!
Here's what happens if you run sound waves through your cornstarch solution:
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Great tip! Thank you, Shannon!
No question, but I do have a comment. Try your local thrift store or Goodwill to find a speaker. I often let my son pick out some cheap electronic to take apart. You could probably find something with a speaker for just a few dollars.
There really isn’t any other substitute… you have to use a speaker for this particular experiment.
What can I use instead of an OLD speaker and a bass?
cooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooollllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll!!!!!!!!!!!!!!!!!!!!!!!!!!
In the trash – it’s just cornstarch and water, and totally safe to dispose of in the garbage.
How can you easily dispose of the slime?
You can color it all you like. And dancing…?
can you color the slime and it will not effect it dancing
My youngest absolutely loved this. He spent 3 hours slowly altering the proportions to see what would make the best slime. He now wants to have a slime birthday party. My husband is so happy about the excuse to play with non-newtonian fluids. 🙂
You need an OLD speaker that you can cover with plastic wrap (so it doesn’t soak the paper cone) – use a bass or sub-woofer. Use the 2:1 ratio of cornstarch to water mixture and lay it on top of the speaker cone on the plastic wrap. Plug the speaker into music (unless you happen to have a function generator you can borrow – but that’s pretty rare) and have fun!
How do we set up the slime so that it will dance?
Very Cool to see the slime “get up and dance!”
Make a thin paste using cornstarch and water.
How do you make the homemade laundry starch?