The use of anthocyanins in red cabbage extracts as pH indicators has long been a popular classroom activity. Flowers, fruits and vegetables contain a diverse range of anthocyanins. This investigation explores further applications of plant-derived dyes including reversible reactions based on oxidation/reduction chemistry and other reactions to illustrate colour changes that are not solely dependent on pH change. By using household materials and plant dyes, this investigation may potentially be completed at home if necessary.
Due to the COVID 19 crisis, ChemEd X videos and software is open access to all educators.
With the current global COVID-19 pandemic, there has been much discussion of “flattening the curve” by social distancing. These ideas can be demonstrated chemically, for example, by the iron-catalyzed decomposition of hydrogen peroxide to produce an oxygen gas foam. Decreased hydrogen peroxide concentrations, representing decreased human population concentrations from social distancing, produce oxygen gas foam, representing cases of illness, at a slower rate. A similar demonstration can be achieved using the popular Diet Coke and Mentos experiment. These simple experiments are best used as stand-alone demonstrations.
In this activity your students will be introduced to the concepts of claim, evidence and reasoning. The activity is POGIL- like in nature in that no prior knowledge is needed on the part of the students.
Like most concepts in chemistry, intermolecular forces takes a bit of imagination and critical thinking to fully comprehend and apply when explaining a variety of situations. Though demonstrating the presence of these forces in a simple and explicit manner can easily be done, I wanted to change how I introduced IMFs a bit this year by focusing on a more data-to-concepts approach.
It is not known why people develop allergies to nickel and there is no cure. The best course of action to prevent an allergic reaction is to avoid contact with products containing nickel. This article will explain how to make an easy and cheap nickel detection device that will limit or eliminate the risks of exposure to sources of nickel using some interesting classic chemistry.
Biosorption is a method that can be used for the removal of pollutants from wastewater, especially those that are not easily biodegradable. This experiment uses citrus fruit peels as part of a iodometric titration to conduct a wastewater treatment binding copper.
I came across an interesting Journal of Chemical Education article that explains how it is possible to crosslink sodium alginate, leading to the formation of calcium alginate beads. Calcium alginate beads are hydrogels and one of their uses is to immobilize enzymes in their structure. I thought it would be cool to immobilize some lactase enzyme onto calcium alginate beads and investigate its ability to hydrolyze lactose.
Is it time for us as chemistry teachers to move beyond the Le Châtelier Principle as justification for why disturbances to equilibrium systems cause particular “shifts”? The author shares his new approach to teach equilibrium and provide his students with a more rigorous understanding of the concept.
The authors of the recent Journal of Chemical Education article, PolymerDay: Outreach Experiments for High School Students, offer a collection of interactive polymer activities designed to be part of an all-day outreach event for high school students. For teachers that might use the activities on separate occasions and/or as part of their curriculum, the authors recommend an accessible resource to support that work.
This is an ACS Authors' Choice article and is open access to all.