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Your kids are going to love watching a styrofoam cup disappear right before their eyes as it is seemingly eaten by a harmless liquid. This liquid is any variety of citrus essential oil. Not only does it eat through styrofoam in a matter of minutes, it also smells lovely. We drew faces on our cups so it looked like the oil was eating through the brains of our little characters. It’s Halloween season, may as well get in the spirit, right?
Total Time: It took about 20 minutes for this experiment to go to completion
Difficulty: Supervision is suggested when the kiddos are handling the essential oils, just to make sure they don’t get it in their eyes or pour half the bottle onto the styrofoam. Overall, a very simple experiment though.
Materials You Need:
Permanent markers (if drawing faces on the cups)
Citrus essential oils (we used Lemon, Lime, Orange, and Citrus Bliss, but feel free to use any citrus oils you have on hand)
- Draw a spooky face on an upside-down cup.
- Carefully drip 1-2 drops of essential oil onto the cup.
- Wait a few minutes and watch it eat a hole right through the brains of your cup guy!
All of the oils we used worked comparably well. The lemon and lime probably worked the best, though. The active chemical in this reaction is called limonene. It is found in the peel of citrus fruits. Since essential oils are so highly concentrated they have the ability to eat through styrofoam while you wait! As a side note, toluene, benzene, and acetone will also dissolve styrofoam. However, these solvents are toxic and shouldn’t be handled by children Plus they don’t smell nearly as yummy as citrus oils do.