When I do science outreach with kids, I encourage them to get creative and try different ratios of ingredients in experiments like Mad Scientist’s Green Slime, to see how their results will vary. Will they get stretchy goo, or bouncy balls?
This morning, I decided to explore the kid in me and see what fun new experiment I could come up with, using the ingredients for polymer slime. After lots of giant failures, I came up with a fun way to combine two experiments: Mad Scientist’s Green Slime and Paper Bag Volcano. My kids gave it a big thumbs up and gave the experiment a fun name. Hope you like it too!
For this experiment, you’ll need: Borax laundry detergent (powder), baking soda, glue, vinegar and a full small 8oz plastic water bottle.
1. Remove the label from the bottle, take the lid off and pour out about 2oz of water.
2. Add 1 tsp. Borax and 5 tsp. baking soda to the water in the bottle (we used a paper funnel.) Put lid back on and shake well. Label bottle Borax/Baking soda.
3. Mix together 2 Tbs. vinegar, 2 generous Tbs. glue and a few drops of food coloring. Mix well and transfer to a pouring container, like a paper cup with one side pinched into a spout.
4. Shake the bottle of Borax/Baking soda solution up again and set it in a large bowl. Remove the lid from the bottle.
5. Pour the glue/vinegar solution into the water bottle very quickly, all at once.
6. When your bottle has stopped “erupting,” squeeze the foamy slime out of the bottle into the bowl and mush it all together.
7. Enjoy your foaming slime monster! What would happen if you added glitter? Does the amount of glue you added make a difference? What if you added more?
The science behind the fun: Polymers are long chains of molecules, like a long string of beads on a necklace. In fact, polymer means “many pieces!” Glue contains a chemical called polyvinyl acetate, a polymer that is runny when you mix it with water or vinegar. However, if you add Borax detergent, a crosslinker, it makes all of the glue molecules stick (or link) together in a big glob.
When you mix together baking soda (sodium bicarbonate) and vinegar (acetic acid), you’re doing a chemical reaction. One of the products of this reaction is carbon dioxide gas.
In this experiment, when we pour the glue/vinegar into the baking soda/Borax solution, we mix baking soda and vinegar at the same time as we link glue molecules together, trapping gas bubbles inside our gluey polymer slime. Your “slime monster” escapes as the slimy bubbles push their way out of the bottle under increasing pressure.
Feel free to share this experiments with your friends. If you’re sharing it on a website, please link back to this post though, since it’s an original experiment!