Video Demo: Disappearing Cup

disappering cup smallMany of the demos that I use in teaching chemical reactions are taken from a terrific book called A Demo A Day–Chemical Demonstration Book. The book contains a year’s worth of chemistry demonstrations that are easy to follow and to use. This demonstration shows the concepts of polymers. Styrofoam is an example of a polymer. A polymer is made up of monomers. You can think of a monomer as a Lego piece. When you connect the Lego pieces together you have a polymer. You can take a Styrofoam cup and place it in a petri dish of acetone. Push down on the cup and the cup seems to disappear! The acetone is breaking the bonds between the monomers.

Precautions: Wear goggles, use in a well ventilated area. Caution: acetone is flammable.

materials needed
disappering cup

view Quicktime video version

3 Responses to “Video Demo: Disappearing Cup”


  1. 1 Bob Jan 4th, 2007 at 8:31 pm

    Awesome!!!!!!!!!

  2. 2 sciencefix Jan 5th, 2007 at 3:43 am

    Thanks!

  3. 3 Peter Transki Jan 27th, 2007 at 1:51 am

    That s so wierd!!!

Leave a Reply