equilibrium

From JCE - A demonstration for challenging students' thinking on acid-base chemistry and equilibrium

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.

JCE 95.04 April 2018 Issue Highlights

Placing Chemistry into a World Context

The April 2018 issue of the Journal of Chemical Education is now available online to subscribers. Topics featured in this issue include: service-learning, safety, investigating student understanding of solutions, environmental chemistry, green chemistry, waste management, acid-base chemistry, natural products, materials science, activities and laboratory investigations, teaching resources, diving into the archives: marine chemistry.

Book Suggestion: The Alchemy of Air

One of my goals for 2017 was to read more chemistry non-fiction. I accomplished that with three and a half books read. That doesn't seem like much, but given how busy I've been lately it was quite an accomplishment! I offer a brief review of my most recent book here, "The Alchemy of Air" by Thomas Hager.

Moving Beyond Le Châtelier

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.

An Activity to Demonstrate the Principles of Chemical Kinetics and Equilibria

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.

Time required: 

30 - 45 minutes of class time

 

Chemical Thinking Interactives

As part of a two-week Chemistry Modeling Workshop™ in Houston, TX, I had the opportunity to read the Journal of Chemical Education article “When Atoms Want” by Vicente Talanquer of the University of Arizona. I researched Dr. Talanquer and discovered he created a collection of simulations called Chemical Thinking Interactives (CTI). These digital tools illustrate many chemistry topics with a focus on the particulate nature of matter.

A New Standard: Refine the Design of a Chemical System by Applying Engineering Principles

Teachers are accustomed to implementing new learning standards developed by state or national leaders. My state, Georgia, chose not to adopt the newest national standards. State leaders wrote the “Georgia Standards of Excellence” instead. Full implementation of the GSE begins in the 2017-2018 school year.

Big Ideas in AP Chemistry: Connections Among Thermodynamics and Equilibrium

I have a confession: thermodynamics is not my strong suit. The data set I got from the College Board confirmed my lack of confidence in the summer of 2015. With the hope of improvements, I spent some time revamping my thermo unit and I implemented it near the end of last school year. I will share an activity that I feel was quite formative for students and for me in making connections among thermodynamic principles and equilibrium.

 

Titration of an Esterification Reaction to Determine Equilibrium Constant

This activity was submitted for a 2016 ChemEd X Call for Contributions soliciting input regarding the big ideas being put forth by organizations like AP. The author shares a lab activity that relies on connections - between stoichiometry, esterification, equilibrium, kinetics, titrations and uncertainty of calculations. He also shares the resources he created. 

Time required: 

Three class periods

Day 1: setup of equilibrium mixture; roughly 30 minutes

Day 2: titration of equilibrium mixture (approximately 1 week after Day 1); roughly 60 minutes

Day 3: calculations; variable time required - typically 30-90 minutes depending on the student group