Given a guiding question, students determined what they wanted to test, did the experiment and got their CER boards ready for review. Instead of a regular argumentation session, we had a glow and grow session, where students had to provide positive and negative feedback for each board.
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.
Whether you are introducing collision theory or something more demanding like reaction order, the reaction between sodium thiosulfate—Na2S2O3 and hydrochloric acid can provide a consistent, accurate, and engaging opportunity for investigating these topics.
I taught my students how to use the method of initial rates. I taught my students rate laws. However, they strugged to differentiate when to use what method. Upon further probing, they struggled to articulate why one might use one method over the other. They could parrot back some ideas ("The rate law tells you about the particles involved in the rate determining step of the reaction."), but I wasn't convinced of mastery and connections.
In one of my last blog posts I wrote of how I sometimes enjoy ending a unit with a series of demonstrations and using them to elicit a dialog between the students and myself to check for understanding. It is always a fascinating experience to hear the misconceptions that many students have the day before the test.
