Is it possible to use materials found in high school chemistry labs to extract and subsequently detect cocaine on dollar bills? Let me know what you think after reading this blog post!
Endowing Inspiration
The August 2016 issue of the Journal of Chemical Education is now available online to subscribers. Topics featured in this issue include: blue bottle reaction revisited; precollege professional development; chemical education research on intermolecular interactions and bonding; integrated courses; activities involving kinetics, enzymes, and gases; nanomaterial & polymer laboratories; organic synthesis; NMR teaching resources; book recommendations for summer reading.
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.
Solution to Chemical Mystery #6 is presented. Also, concepts related to the chemical can crush demo are briefly discussed.
In a dramatic movie trailer voice: “The Boiling Point. Gone without a trace. Or were they? The scene… a mystery. Had they disappeared? Been broken up into unrecognizable pieces? Can our hero find the answer? Or will it be too late?”
One of my favorite things to talk about with my colleagues is the use of lecture demonstrations in teaching. There seems to be a push in my district to stop using chemicals whenever possible and get to computer simulations and video in place of wet chemistry. I don’t think they are thrilled with me since I can’t envision ever taking the chemistry out of chemistry.
The chemistry of silver and the process in which silver becomes tarnished is explored. Take a new look at an old JCE Classroom Activity.
In my IB Chemistry class, my seniors were finishing up independent investigations for their Internal Assessment a few weeks ago when something cool happened. One of my students was using silver nitrate and potassium chromate for a titration. This is notable to the story here because the endpoint is marked by the formation of silver chromate as a precipitate, with a deep reddish color. I overhead the student showing his reaction to another student, with both of them commenting on the cool colors involved.
A description of a quick and easy lesson that is sure to add some spark into your next lesson on stoichiometry.