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 an effort to better understand my high school students' knowledge of what is happening during phase changes, heating curve calculations, and the ever popular can crush demo, I run them through a series of activities. First, I ask my students "What Temperature Does Water Boil At?"
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?
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!
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.
Solution to Chemical Mystery #6 is presented. Also, concepts related to the chemical can crush demo are briefly discussed.
Want to try an easy, yet interesting chemistry experiment this winter? Try this: Blow some bubbles into the outside winter air and catch one of the bubbles with a bubble wand.