There’s just something irresistible about sinking your hands into a bowl of perfectly mixed cornstarch and water. This popular science activity has nicknames like Oobleck and Cornstarch Quicksand, but scientists refer to this substance that behaves like both a solid and a liquid as a Non-Newtonian fluid. Steve Spangler calls it the perfect science demo for his February 2008 appearance on the Ellen DeGeneres Show.
When Steve originally discussed the idea of mixing up a batch of cornstarch and water with the producers at the Ellen Show, there was little interest – that’s because he forgot to mention that someone would be walking on it! The challenge was to turn a kid’s kitchen chemistry activity into a large-scale demo. Anyone who has ever played with this cornstarch and water mixture knows that the bigger the batch gets, the harder it is to mix it. If Ellen or someone was going to walk on water, Steve and his team would have to find a way to mix up a huge batch – that’s when the team of mixologists pitched the idea to the Bonanza Cement company.
Now is a good time to pause and mix up your own batch of Non-Newtonian goo so that you can better understand and appreciate what happened next… and once your hands sink into the bowl of goo, you’ll be hooked ]
- Pour approximately 1/4 of the box of cornstarch into the mixing bowl and slowly add about 1/2 cup of water. Stir. Sometimes it is easier to mix the cornstarch and water with your bare hands — of course, this only adds to the fun.
- Continue adding cornstarch and water in small amounts until you get a mixture that has the consistency of honey. It may take a little work to get the consistency just right. As a general rule of thumb, you’re looking for a mixture of roughly 10 parts of cornstarch to 1 part water. Notice that the mixture gets thicker or more viscous as you add more cornstarch.
- Sink your hand into the bowl of cornstarch goo and notice its unusual consistency. Compare what it feels like to move your hand around slowly and then very fast. You can’t move your hand around very fast! In fact, the faster you thrash around, the more like a SOLID the gooey stuff becomes. Sink you entire hand into the goo and try to grab the fluid and pull it up. That’s the sensation of sinking in quicksand!
Important – READ THIS!
Ironically, the cornstarch will not stay mixed with the water indefinitely. Over time, the grains of cornstarch will separate from the water and form a solid clump at the bottom of the plastic storage bag. It is for this reason that you must not pour this mixture down the drain. It will clog the pipes and stop up the drain. Pour the mixture into a zipper-lock bag and dispose of it in the garbage.[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][ultimate_heading main_heading=”But We Need 250 Gallons of This Stuff” alignment=”left”][/ultimate_heading][/vc_column][/vc_row][vc_row][vc_column width=”2/3″][vc_column_text]Steve Spangler’s goal was to mix up a batch large enough to fill a small swimming pool and then to attempt quick run across the surface. The weight of someone’s body should cause the liquid to turn into a solid for a split second, allowing the person to literally run across the surface. Well… that’s the theory.
Let’s start with the pool. The props guys (a very creative and talented team of people who can pull of anything) constructed a container that was 7 feet long, 3 feet wide and about 1.5 feet deep, which holds about 240 gallons of water. According to the 10 to 1 ratio, Steve would need roughly 2,400 pounds of cornstarch to mix with the 240 gallons of water.