No, it’s a non-Newtonian fluid!

The cornstarch and water experiment is perhaps one of the most entertaining and fun you can do. You will see how you will not be able to avoid a smile if you measure yourself to the task of investigating the properties of non-Newtonian fluids.

You will need the following materials:

✔ 3 cups cornstarch or cornstarch flour
✔ 1 cup of water
✔ 5 drops of food coloring (optional, add to water)
✔ 1 gallon container or airtight bag

Process

Rub a little cornstarch between your fingers, doing so you will feel its silky texture. Then, in an airtight container or bag, add a cup of water to three cups of cornstarch, if you wish you can also add food coloring. Gradually add the cornstarch to the water, mixing it with a spoon or your hand. If you can take a handful of the mixture and knead it into a solid ball between your hands… you’ve got the right consistency! Now, hold out the palm of your hand and watch the mixture flow through your fingers like a liquid. If for some reason you don’t achieve this consistency, continue adding water or cornstarch. It is important that you know that you should not pour the mixture down the drain as it can get stuck in the drain and ruin your wonderful scientific day. Throw the mixture in the trash.

Discussion

Issac Newton stated that liquids flow at constant and predictable speeds. But the mixture in this experiment does not follow this theory since it can act almost like a solid and flow like a liquid.

So why does this mix act the way it does? The answer is that it is a non-Newtonian fluid whose viscosity changes depending on the shear stress or force you apply to it. The behavior of Newtonian fluids can be described exclusively by temperature and pressure with no other forces involved. An example of a Newtonian liquid is water. Do you think you can give other examples?