Screaming Pennies

Physics Chemistry:	States of Matter, Sublimation
Grade Range:	Elementary School, Middle School
Format:	Hands-on

This is a good way to catch a student's curiosity as they walk by the table or booth. Be sure to prevent students from touching the dry ice!

Materials

Please read the Cryogen Safety section of the Demonstration Safety page before performing this demonstration.

This demonstration requires: Safety glasses, cryogen gloves

Set out the plate or dish, and have a small pile of pennies in one corner of it. Keep the center clear for the dry ice. Put on the safety glasses, and keep the cryogen gloves on the table next to the dry ice.
When a student approaches the table, put on the cryogen gloves and pick out a piece of dry ice from the container. Hold the dry ice on the plate, and ask the student to pick out a penny. Once they do, press the penny into the dry ice. The penny will start making noise!
Set the penny on the opposite side of the plate from the others. Use one or two more pennies while explaining what is going on, and then allow the student to touch the first penny you used. It will be cold!

COMING SOON

This demonstration is often performed with other demos that require dry ice, such as the Tornado Box, the Blood And Buffers, and the Making a Comet demonstrations!