Like most chemistry teachers, one of the first things I go over in the beginning of the year is unit conversions. Students come into my class with all sorts of prior knowledge concerning unit conversions; some good, some bad and some downright ugly.
In Chemical Mystery #7, a can of Coca-Cola was observed to sink in one container of water and yet float in another! This trick made use of the fact that the density of water changes with temperature. See the video below.
Q: Does an unopened can of soda pop float or sink in water?
A: It depends!
See if you can figure out what is happening in this twist on the classic floating-and-sinking soda can experiment.
Each spring my Local Section of The American Chemical Society (ACS) hosts a rigorous two part exam as part of the selection process for the The International Chemistry Olympiad (IChO) IChO is an annual international competition for the world’s top chemistry students. Each year, nations from all over the world will send teams of four to compete for top honors.
45 minutes
Effective Student Engagement
The September 2015 issue of the Journal of Chemical Education is now available online to subscribers. This issue includes articles on flipped classroom; introductory and general chemistry; organic chemistry activities; biochemistry demonstrations and labs; computer-based learning; chemical education research; from the archive: chemistry in context.
In Chemical Mystery #5, I used chemistry to give the illusion that water can be lit on fire. Here is the solution to that mystery.
The video displays a neat trick you can do for your students. What do you suppose is the secret behind this trick? Hint: >It has to do with chemistry!
Did any of you guess what was going on in Chemical Mystery #4: The Case of the Misbehaving Balloon? In this experiment, several balloons were placed in liquid nitrogen. Most of these balloons shrunk tr
Although many students have been exposed to the concept of density before reaching my Chemistry class, I always start the year with this POGIL-like activity.
Approximately one hour including the debrief (I recommend holding a whole-class discussion for the summarizing questions that follow the What is density? activity and a selection of mathematical computation problems from the How can you calculate density? activity.)
One day during class I presented the disappearing rainbow demonstration and explained the chemistry behind it. After doing so, I had a student ask me if a particular bartending trick called “rainbow shots” was done in a manner similar to the way the disappearing rainbow demonstration is performed.