Tom Kuntzleman's blog

Chemical Mystery #9: Liquid Nitrogen vs. Dry Ice

Bucket launch

A 2L soda pop bottle is filled about one-third full with either liquid nitrogen or solid carbon dioxide (dry ice) and water. The bottle is sealed and a plastic bucket is placed on top. Do you think the liquid nitrogen or dry ice and water will make the bucket go higher? Can you explain the results using chemistry?

Dry ice in five different liquids

Dry ice in five different liquids

You probably know what happens when you place dry ice in water. Do you know what happens when dry ice is placed in acetone or glycerin? Read this and find out!

The Dry-Ice-in-Water Cloud

Cloud formed when dry ice is placed in water

Have you ever wondered where the cloud comes from when dry ice is placed in water? If you think the answer is “atmospheric water vapor”, be sure to read this post because experimental evidence suggests that this explanation is wrong.

Chemical Mystery #8: Go Blue!

Go Blue!

Addition of a white solid to a green solution causes the solution to separate into some truly beautiful colors...

Kool-aid, Cotton, and Intermolecular Forces

Dyed fibers

Red dye #40 found in strawberry Kool-Aid and various cloth fibers can be used in a very simple experiment that can teach students about intermolecular forces. A video is included that describes the experiment and analysis of results. 

Big Ideas at ChemEd X

Shultz's JCE article

In the article “Reactions Catalyzed by an Assault on a Favorite Principle”1, Emeric Schultz (who incidentally taught me General Chemistry, was my undergraduate advisor, and is now a dear friend and colleague) argues the following:

“Although I have read and heard about ‘big ideas’ in chemistry, I have never seen a commensurate effort to work toward a high school chemistry program that starts from…big ideas and works down.”