Learn about the science behind slime

The “slime” or slime has invaded social networks and is one of the favorite crafts of children. But do you know the science behind this fun slimy dough? Discover it here!

To make slime you will need the following ingredients:

✔ 5 ounces (1 medium jar) white or clear glue
✔ ½ teaspoon baking soda
✔ 1 tablespoon of soft contact lens solution or saline. (Must contain boric acid and sodium borate)
✔ 1 container
✔ 1 mixing spoon
✔ Optional: pastry coloring and/or glitter


To make your slime, pour the entire contents of the glue bottle into a container and add ½ tablespoon of baking soda, make sure to mix the ingredients very well with a spoon. Then add 1 tablespoon of contact lens solution. Mix until a dough forms. Take the dough from the container and start kneading it with both hands. If the dough is too sticky, add ¼ tablespoon of contact lens solution and continue kneading.

To add color and sparkle, you can add a few drops of liquid food coloring, as well as glitter.

⛔ Care: Store your slime in an airtight container. When you’re done with it, throw it away, don’t pour it down the drain.


Slime is so much fun to play with as it can be soft, fluffy and stretchy at the same time. This is because slime is a non-Newtonian fluid.

According to Isaac Newton, all fluids have a property known as viscosity. Viscosity describes the thickness of a fluid. For example, honey is much more viscous than water. When the viscosity of a fluid is constant, it is called a Newtonian fluid.

Slime is an example of a fluid whose viscosity is not constant, it changes depending on the applied force. If you pull it apart quickly, applying a lot of force, it becomes very sticky and will break in half. If you pour it gently, applying little force, it will flow like honey or molasses. However, it becomes more viscous when you stir or knead it.

Another non-Newtonian liquid is ketchup or tomato sauce. But this one behaves in the opposite way to slime. Have you ever had to shake the jar because the sauce refuses to come out? This is because the ketchup or tomato sauce becomes less viscous or thick when you shake it.

Variations of this experiment:

You can change the consistency of your slime by adding a little baby oil to the mix, which will make it smoother. If you want it to be fluffy, just pour shaving foam on it.