This post describes a simple way to generate blue, green, orange, and yellow copper complexes, and to use these complexes to introduce students to the effect of temperature on chemical equilibria. The protcol avoids the use of caustic agents, allowing the experiments to be conducted by students as a laboratory-based investigation.
What's a better way to start the new school year than with some new experiments? Learn how to use a variety of color changing experiments to teach students about the Diet Coke and Mentos experiment, acids, bases, chemical and physical changes, and climate change.
The solution to Chemical Mystery #17 is presented. Were you able to use your chemical knowledge to explain the results?
Solutions of copper (II) dissolved in acetone are easy to prepare, and can display orange, yellow, green, and blue color depending upon conditions. Such solutions allow for a variety of demonstrations and experiments that illustrate principles of chemical equilibrium.
My top 5 reasons for using Green Chemistry in my classroom along with a few examples of replacement labs that follow Green Chemistry principles.
For dynamic equilibrium, I like to use a physical analogy that pits students against each other in a classroom-wide “snowball” fight. Not only is this activity great for building students’ conceptualization of dynamic equilibrium, it is also really fun!
The solution to "Chemical Mystery #16: A Red, White, and Blue Chemistry Trick for You!" is presented. How this experiment can be used as a springboard to carry out a simple quantitative analysis of salt solubility is also discussed.
I was drawn to an article by Eilks, Gulacar, and Sandoval about Acid-Base Chemistry and Chemical Equilibrium in the April 2018 issue of JCE. The title of the article is "Exploring the Mysterious Substances, X and Y: Challenging Students' Thinking on Acid-Base Chemistry and Chemical Equilibrium." The premise of the article is to demonstrate how an instructor may use a group of compounds (zeolites) to "elaborate on the behavior of solid state acids and bases" while revisiting LeChatelier's principle.
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.
A classroom activity to demonstrate the principles of chemical kinetics and equilibria and the utility of the mole concept is described here. The activity involved no hazardous materials or complex equipment and can be enjoyed and appreciated by general studies students as well as chemistry majors.