Eis 5: States of Matter
Oobleck
There are the common states of matter--solid, liquid, gas--and then there are the ones that might make you believe in aliens--like this non-Newtonian fluid on a speaker cone.
The very unofficial, but fun, name for this crazy alien dance party is oobleck. Oobleck is a non-Newtonian fluid, which means that its properties change depending on the conditions. Under normal pressure conditions it is a liquid, but, under high pressure, it becomes more like a solid. Really, everything becomes somewhat more solid under high pressure, because the molecules are getting squeezed together, but perhaps the biggest difference with oobleck is how minimal and localized that pressure can be. Sound waves bouncing through a speaker can make it more solid. Running across it can make it more solid:
And, as you’ll find out, even just touching it, moving it around, or playing with it makes it more solid.
Materials
- 1/2 cup water
- 1 cup cornstarch
- Spoon
- Cup or bowl
- Food coloring (optional)
Directions
1. Add 1 cup cornstarch to a bowl (you can change the amount if you want, but the ratio of cornstarch to water should stay the same).
2. Slowly mix as you add ½ cup of water (per 1 cup cornstarch) to the cornstarch.
3. Feel the mixture with your fingers, or poke it with the spoon.
4, Squeeze it tightly in your hand, or try scooping it quickly with the spoon. What happens?
5. Now add some food coloring and mix it around. How does the color spread?
6. Play around with it and have fun! Just don’t go ruining any of your speaker sets by pouring it on there :). Always be sure to get the permission of your relevant responsible adult before trying anything unusual.
2. Slowly mix as you add ½ cup of water (per 1 cup cornstarch) to the cornstarch.
3. Feel the mixture with your fingers, or poke it with the spoon.
4, Squeeze it tightly in your hand, or try scooping it quickly with the spoon. What happens?
5. Now add some food coloring and mix it around. How does the color spread?
6. Play around with it and have fun! Just don’t go ruining any of your speaker sets by pouring it on there :). Always be sure to get the permission of your relevant responsible adult before trying anything unusual.
Gloop
Gloop—another unofficial, but fun name—is another one of those things that doesn’t fall neatly into our categories of solid, liquid, and gas. It is called a viscoelastic liquid, because it is primarily a liquid but also has properties of an elastic solid (like a rubber band).
Gloop can also be conveniently made with common household supplies! These materials aren’t quite as common as the ones needed for oobleck, but they’re pretty cheap and can be found easily at most superstores and online. This activity is not mandatory if you can’t get a hold of the supplies, but it is super fun!
Gloop can also be conveniently made with common household supplies! These materials aren’t quite as common as the ones needed for oobleck, but they’re pretty cheap and can be found easily at most superstores and online. This activity is not mandatory if you can’t get a hold of the supplies, but it is super fun!
Materials
- About 1/4 - 1/2 cup water-based glue, like Elmer’s or another school glue
- 3/4 - 1 cup water.
- About 1 tbsp borax. This can be found with laundry supplies.
- Spoon.
- Two cups or small bowls
- Food coloring (optional)
Directions
1. Mix one part glue (1/4 to 1/2 cup) with one part water (same amount) in one cup or bowl. Add food coloring to this mixture if desired.
2. Add about a tablespoon of borax to about half a cup of water in the other cup or bowl, and stir so that some of the borax dissolves.
3. While stirring the glue-water mix with the spoon, slowly pour some of the borax-water mix into the glue-water mix. You should notice the glue beginning to congeal.
4. Finally, mix the resulting gloop with your hands. Play with it! Have fun.
2. Add about a tablespoon of borax to about half a cup of water in the other cup or bowl, and stir so that some of the borax dissolves.
3. While stirring the glue-water mix with the spoon, slowly pour some of the borax-water mix into the glue-water mix. You should notice the glue beginning to congeal.
4. Finally, mix the resulting gloop with your hands. Play with it! Have fun.
Content contributors: Emma Moulton and Emily Zhang