Boiling Cold

Funded Nov 11, 2013

Thank you very much for donating the funds which purchased a cryogenic liquid dewar. We are now able to receive deliveries of liquid nitrogen from a local supplier to use in our classrooms. The students were very excited to see all of the demonstrations using liquid nitrogen and were wondering what it would take to be able to purchase liquid nitrogen to play with at home!

So far we have used liquid nitrogen to explore the relationships between temperature, states of matter, and the kinetic energy of molecules. Some of the demonstrations I did for the class were making a Pringles can rocket, dipping a balloon in liquid nitrogen, dipping a racquetball in liquid nitrogen and shattering it on the floor, and creating a liquid nitrogen "fountain" with a balloon. Along with the demos, we compared what we could see to a computer model of molecules moving at different speeds. Students then constructed explanations for their observations. Having a concrete representation for the students to see, hear, and feel helped the more abstract representation that the computer model provides make sense. Later this year, I plan on using liquid nitrogen and water for a simple energy transfer lab.

Last but not least, I froze some mini-marshmallows in liquid nitrogen. The students enjoyed eating them and watching the water vapor from their breath condense into vapor. They weren't satisfied until they figured out how to blow the vapors out of their noses. One of my first period students said this lesson was, "the best day in chemistry all year!" Thank you again for making this learning experience possible.”

With gratitude,

Ms. Jaehrling