Take a holiday from "serious" science and have fun with these slime recipes. Plus see the amazing properties of Thinking Putty in our Thinking Putty video.
Making slime has long been a favorite chemistry activity. Who doesn't like to play with something gooey and squishy and, well, slimy, every once in awhile? This issue will show you how to make slime with household ingredients, or how to step it up a notch with a liquid polymer called polyvinyl alcohol.
This is a fun and easy slime to make. Make it with white glue for opaque slime, or glue gel for translucent slime.
The glue has an ingredient called polyvinyl acetate, which is a liquid polymer. The borax links the polyvinyl acetate molecules to each other, creating one large, flexible polymer. This kind of slime will get stiffer and more like putty the more you play with it.
Store it in a plastic bag in the fridge, to keep it from growing mold.
This slime is similar to the one above, but creates a less rubbery and more transparent slime. This is the real gooey deal! (This slime is non-toxic, but still keep these chemicals away from unsupervised children and wash your hands after playing with the slime.)
While water is a liquid made up of individual H2O molecules, polyvinyl alcohol is formed of long chains of connected molecules, making it a liquid polymer. (The term polymer comes from the words for "many parts.") The borax acts as a "cross-linker," linking the individual PVA chains to each other so they connect to form a blob of slime. It does this linking job when the borax molecules form hydrogen bonds with molecules present in the PVA chains. (The partial positive charge of hydrogen atoms attracts the partial negative charge of oxygen atoms.) Since hydrogen bonds are weak, they can break and reform as you play with the slime or let it ooze on a flat surface.
Your slime will last for a while if you seal it in a plastic bag and keep it in the fridge.
Other fun home recipes:
Everyone loves playing with a little silly putty, but Thinking Putty is even better! It's the ultimate putty that can stretch, squish, tear, smash, bounce, make noise, and change color.
Even if you don't have some, you can see it in action with our Thinking Putty video.
Putty is a Non-Newtonian substance, which means that it doesn't follow the theory of viscosity that Newton observed. Viscosity is the "thickness" of a liquid, or its resistance to flow. (Honey, for example, has a much higher viscosity than water.) Thinking Putty, while sometimes having properties of a high-viscosity liquid, also has certain properties of a solid. Like a liquid, it won't hold its shape, although because of its high viscosity, it moves very slowly. Unlike most liquids, however, Thinking Putty changes its behavior based on the amount of force applied. If you pull it gently, it will stretch; if you pull it forcefully, it will tear. If you push your finger in gently it will sink deep into the putty, but if you jab it hard your finger will bounce right off. When you apply the ultimate force—hitting it with a hammer—it acts exactly like a solid and shatters as though it were ceramic. (But then you can pick up the pieces and stretch and smash them like putty again!)
Stretching, Tearing, and Popping:
One of the most fun things to do with putty is just to stretch, twist, squish, and mold it into shapes. While you're at it, you can make a little noise.
Some Thinking Putty is thermo-chromatic, meaning that it changes color with changes in temperature! Just playing with the putty in your hands will warm it up enough to change colors, but you can also use a hairdryer to change its color in quick, dramatic fashion. Then use something cold, like ice or compressed air, to "draw" on your warm putty. If you just stick a piece of ice onto the putty, you'll see the cold color "glow" through the ice cube.
Bouncing & Smashing: