Simple methods to prepare liquid air are described. In addition, ways to test the properties of liquid air and other liquefied gases are explored.
The solution to Chemical Mystery #11, which involves the Leidenfrost Effect, is presented.
What happens if you place metal that is glowing orange-hot into some water? Watch this video and find out!
I recently watched a video in which a chemist (who goes by the nickname “NurdRage”) activated a chemiluminescent reaction by vapor deposition. I wanted to try it out for myself! Unfortunately, oxalyl chloride is toxic, corrosive, and a lachrymator. Thus, the experiment conducted by NurdRage needs to be conducted in a hood, and it is not particularly amenable to simple presentations. I began to wonder how I could create this vapor activated chemiluminescence using simple materials.
In Chemical Mystery #10, plastic straws are observed to “magically” change color when waved in the air. Check out the explanation and the video.
In this simple trick, colors are made to "magically" appear and disappear on a straw. This science experiment is very easy to do...if you know your chemistry!
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?
In one of my last blog posts I wrote of how I sometimes enjoy ending a unit with a series of demonstrations and using them to elicit a dialog between the students and myself to check for understanding. It is always a fascinating experience to hear the misconceptions that many students have the day before the test.
There are occasionally discussions amongst educators about the efficacy of using technology in the classroom. Does it really make a difference? One train of thought is looking at the use of technology through the SAMR lens. Is the technology simply a Substitution? Or does it Augment the learning compared to previous methods of learning the same material. Maybe the use of technology Modifies the learning tasks. Or will the technology actually Redefine the learning by allowing the student to interact with knowledge in a way that is impossible without this technology. With this in mind, I set about to use an iPad app and an online simulation to introduce my IB Chemistry students to the concept of Maxwell-Boltzmann distribution curves. I'm not sure exactly where it fits on the SAMR continuum, but without the simulations I could only show my students the graphical representation of the Maxwell-Boltzmann distribution curve. By using the simulations, I am attempting to help my students develope a deeper understanding of them.
Conducting experiments with liquid nitrogen experiments is a sure-fire way to energize many chemistry lessons. Unfortunately, getting access to liquid nitrogen can be a bit difficult. I happen to purchase liquid nitrogen from Airgas; you might be able to find a branch near you here.