The Disappearing Cup

DESCRIPTION:
Acetone dissolves a Styrofoam cup because of the principle like dissolves like.

TOPICS COVERED:
polarity
solubility

MATERIALS NEEDED:
– Styrofoam cup
– acetone

PROCEDURE:
1. place the cup on a surface that won’t be harmed by acetone
2. squirt the cup with acetone

ADDITIONAL COMMENTS:
Instead place 2 cups in 2 beakers. Ask for volunteers to see who can fill up their cup first. Give one a water squirt bottle and one an acetone squirt bottle.

SAFETY:
Acetone is flammable, keep away from open flames and always wear safety goggles.

REFERENCES:
Summerlin, L.R.; Ealy, J.L. Chemical Demonstrations: A Sourcebook for Teachers; Oxford University Press: Oxford, 1988; Vol. 2, pp 96.

STORY:
For smaller children it can be treated like a magic trick, i.e. “I’m going to make this cup disappear!”

Handout