Kids, want to do an experiment than can be considered as more on the icky side? While “Glitter Slime” doesn’t sound so bad, we are going to use it as a model for trapping allergens. One way that our noses keep allergens like pollen, spores and dust from our lungs is to use a sticky, slimy material called mucus. Breathe air containing these particles through your nose and it gets stuck in the mucus, becoming safely trapped. This helps us from getting sick. The glitter in the slime will imitate this trapping. We have discussed making slime by various methods in this column before (5/94, 12/94), but we’ll repeat one of them here with some important modifications.
Please note: All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.
Pour 2 tsp water and 1 tsp clear gel glue into a small ziplock bag. Seal the bag and squeeze the bag with your fingers until the contents are thoroughly mixed. Now make a borax solution as follows. Pour ¼ cup of water into a plastic cup. Add ½ tsp borax to the water and stir with a plastic spoon until dissolved. Add two drops of food coloring and stir that in. Add 1 tsp of the borax solution to the glue in the ziplock bag. Seal and mix again. Now you can open the bag and remove the slime. How does it feel? Put the slime back in the bag and add ¼ tsp glitter. Seal and mix. Open the bag and observe the contents. Does the glitter stick to the slime? You can use glitter gel glue if desired, although the concept of the glitter sticking to the slime like dust in mucus is somewhat lost. You can also use 1 tablespoon small Styrofoam craft beads in clear gel glue instead of glitter. The beads versus the glitter not only feel different, but they can also represent the different sizes of spores versus dust, for example.
So what is the chemistry here? The glue-water mixture has very long chains of molecules linked together called polymers. In this case they are called polyvinyl acetate. When borax is added, the chains link together and a slimy glob forms. Glitter is not easily removed from the sticky substance. The slime represents mucus that is in our bodies. Natural mucus contains sugars and proteins, which are also long-chain molecules. Mucus is not only in our noses; it also coats the insides of our stomachs. Without a protective coating of mucus there, the powerful acids used to digest our food would also digest the stomach!
As for cleanup, pour borax down the drain and throw everything else away in the trash, including the slime. Your slime can be stored in an airtight container for a few days to prevent it from hardening. (And, in case you need to know, hardened slime can be washed out of clothing with warm soapy water).
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Kathleen Carrado Gregar, PhD, Argonne National Labs
[email protected]
February 2005
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References: ACS National Chemistry Week 2004 “Celebrating Health & Wellness”, Celebrating Chemistry NCW 2004 newspaper, page 8.
Facilitator tips found on: www.chemistry.org/portal/resources/ACS/ACSContent/ncw/PDF/ncw_04_facilitatortips.pdf
