I facilitate a working group of chemistry teachers in the New York area and we recently created our own activity surrounding the topic of oxidation. The goal of the probe was to force students to think about what the meaning of oxidation is, as well as to allow students to engage in the science and engineering practice of argumentation. This was an introductory lesson to my oxidation and reduction unit prior to students learning the terms oxidation and reduction.
You are likely aware that diamonds are converted - albeit slowly - to graphite under normal conditions. Thus, diamonds don't last forever, in contrast to the popular advertising slogan. However, did you know that you can use chemistry to prove that diamonds are not forever? It's simpler than you think...
Erica Jacobsen shares highlights from the June 2017 issue of the Journal of Chemical Education that are of special interest to high school chemistry teachers.
I found a version of this demonstration online a couple of years ago. I admit, when I first tried it with my class it was mostly for a crowd pleaser to demonstrate the activity series of metals, but I then became very intrigued by the processes occurring. The original source only referenced the “single replacement reaction” between Mg(s) and AgNO3(aq). Therefore, when I saw a grayish product (silver) I was not surprised. However, I was surprised by the white flash and the production of a white product, which were reminiscent of the classic combustion of magnesium demonstration. This led to some research and my conclusions that follow. Read through to the end and you will find a video of the demo.
I have used several different versions of the Silver Mirror or Tollen's Test lab. I am sharing the method that has proven to be the most reliable for me. The solutions should be made fresh, the directions must be followed closely and timing is very important. I like the fact that relatively small amounts of the chemicals are required, but as always you must be vigilant with safety precautions.
A description of a quick and easy lesson that is sure to add some spark into your next lesson on stoichiometry.
This lab was written as part of the Target Inquiry program at Grand Valley State University in Michigan. Students build an electrochemical cell, learn about the symbolic equations used in electrochemistry and manipulate a model representing the particulate level of what is happening during the electrochemical process.
The reaction of a copper penny (minted pre-1982) and concentrated nitric acid (15 M) is shown. Red-brown nitrogen dioxide is generated and some of the copper dissolves to form a blue solution of copper(II) nitrate.