Cornstarch and Water

This experiment uses cornstarch and water to create "oobleck," a non-Newtonian fluid that behaves like a liquid when poured but like a solid when struck or squeezed. It provides a hands-on way to explore suspensions and unusual fluid dynamics.

1. Pour cornstarch into a large bowl. First explore its dry texture by feeling it with your hands.
2. Mix water slowly into the cornstarch, about ½ cup of water per cup of cornstarch. Add food coloring to the water first if desired.
3. Stir and knead the mixture thoroughly with your hands until it flows slowly when at rest but can be rolled into a ball when squeezed.
4. Experiment with the mixture: press it quickly, punch it, let it drip through your fingers, or place objects on it to see how it behaves.
5. When finished, dispose of the oobleck in the trash, not the sink.

The science of cornstarch and water - Massachusetts Institute of Technology (MIT):

Cornstarch Walk on Water - Cool Science Experiment - Sick Science!:

📄 Oobleck – The Cornstarch And Water Experiment - Science Bob: https://sciencebob.com/oobleck-the-corn-starch-and-water-experiment/#google_vignette

• Make a larger batch and try walking across it quickly in a shallow container.
• Test the effects of adding more or less water to adjust its thickness.
• Compare oobleck with other household non-Newtonian fluids like ketchup or slime.

• Oobleck is safe to touch, but avoid eating it.
• Food coloring may stain skin, clothing, or surfaces—use protective coverings.
• Do not pour oobleck down the drain; it can clog pipes. Dispose of it in the trash or mix into soil.

• Why is oobleck called a non-Newtonian fluid? (Because its viscosity changes depending on the amount of pressure applied, unlike Newtonian fluids which have constant flow rates.)
• What happens to the cornstarch grains under pressure? (They lock together, resisting movement, making the mixture behave like a solid.)
• Why does oobleck eventually settle if left alone? (The cornstarch particles are suspended, not dissolved, so they sink over time.)
• What real-world materials or situations act like non-Newtonian fluids? (Examples include quicksand, wet sand, ketchup, and some industrial fluids.)