- Students will experiment with a colloid, and learn about non-newtonian fluids.
- Students will learn about viscosity.
- Vocabulary: Colloid, viscosity, fluid, solid, liquid, non-newtonian
- Bartholomew and the Ooblek, Dr. Seuss
Consumable supplies to gather and/or purchase:
- Food coloring (optional)
- Dixie cups
- Invite students to mix cornstarch and water together in their baggies to make a thick paste (about a 1:2 ratio of water to cornstarch, but can be variable).
- Once students have successfully created the ooblek, ask them to describe its properties: Is this a solid or a liquid? What are some things about it that act like a solid? What are some things that act like a liquid?
- Background: Ooblek is a colloid—a suspension of solid particles in a liquid. Other notable colloids include milk, ketchup, and mayonnaise (ever notice how hard it is to get ketchup out of the bottle?). Colloids aren’t really solids or liquids—they have some properties of both. They resist flowing when pressure is applied, or when trying to be poured quickly, but if you allow the ooblek to slowly drip out of your cup or bag, it will flow!