Oobleck Recipe
1 cup water
1 ½ – 2 cups corn starch
1-2 drops of food coloring of your choice
Place the water in a bowl or cup. Add the food coloring to the water. Then slowly add the corn starch stirring after each addition, until the Oobleck is the right consistency. It should be able to flow through your fingers, but still feel solid when you press down on it with your hand. Enjoy! You can keep the Oobleck in a Ziplock bag in the refrigerator for a few days. Dispose of the Oobleck in the trash can...not the sink!
A. Take some Oobleck in your hands and spread your fingers out wide. What happens?
B. What happens when you push really hard on it. Place it in a container and punch it down with your fist. How does it feel?
C. Roll the Oobleck in your hands like a meatball. Then place it in someone else's hand (your your other hand if you are working alone). What are your observations? D. Do you think Oobleck is a solid, liquid, or gas? Why?
Teacher's Corner:
Uncooked corn starch particles are structured in both crystalline and noncrystalline arrangements. When you gently mix the water into the cornstarch, the noncrystall
ine structures begin to absorb most of the water. If you smack or stir it rapidly, you increase the temperature and pressure which causes more noncrystalline structures to form. These new noncrystalline structures absorb more of the water and the mixture becomes even thicker, and it looks more like a solid. When you stop stirring or placing pressure on the Oobleck, the number of noncrystalline structures decrease and water is released, creating the "soupy" mixture. This type of substance is called a "non-Newtonian fluid." It does not behave in the same way as Newton's Third Law of motion states. Even though it has different properties from Oobleck, Ketchup is another example of a non-Newtonian fluid.
