Slime is a non-Newtonian fluid that is dilatant, which means when under stress, the material dilates or expands. Other well known stress-thickening materials are quicksand, wet sand on the beach, some printer’s inks, starch solutions and ‘Silly Putty’.
- Borax powder (not boric acid)
- 100.ml glue (like Elmer’s white or gel glue)
- Food colouring
- Medium-sized bowl
- Small bowl or cup
- Measuring cups
Always wash your hands before and after playing with your slime. Don’t eat the slime or let anyone else eat it. Be careful to only set your slime down on surfaces that won’t absorb the food colouring you added.
Gather your materials and wash your hands, Bowls and mixing equipment can become quite messy, so disposable options are handy.
Mix 1 teaspoon (5 ml) of Borax powder into 1 cup of water (250 ml), creating a Borax solution, and set to the side.
Empty100.ml of glue into a bowl and mix in approximately 100.ml or ½ a cup of water (~125 ml), creating a diluted glue mixture. You could also just refill the glue container to add the water. Put 1-2 drops of food colouring into this mixture, unless you want your slime to be colourless. (Keep your coloured slime away from surfaces that may absorb colour.)
Slowly mix small portions of the Borax solution into the diluted glue mixture. You will be able to observe the change in consistency taking place. Your slime is polymerizing! Keep mixing! You can now pick up the slime mix and knead it with your hands. The more you play with the slime, the less sticky it will become.
Clean up! Store your slime in a zipper-lock bag. Toss it out when it begins to look funky.
What you Learn
This experiment stresses the importance of not mixing chemicals together, even if you think it might be safe or you’ve seen your parents do it before. In this case, two liquid solutions blended together to create an unfamiliar solid.