I started teaching in a chronological order when I began using Modeling Instruction in my classroom. During the second year of "walking in the footprints of the scientists that came before us", I wanted my students to see where they were walking and a colleague and I came up with the idea of making footprints for each of those scientists and posting them on a timeline.
In a previous post I talked about an equation balancing lab that I have been doing with my students involving building molecular models. This time I would like to focus on another lab that I have developed for my model kits.
Here is what I told my students as we were studying gas laws. I have a bag of potato chips at see level and then I go to Denver where the pressure is less? What happens? Draw and build a model on your whiteboard.
A quick search on Amazon for a package of 144 ping pong balls and a trip to the arts and crafts store for paint, magnets, and glue and I was ready to start making my own class set of model kits.
I am a very firm believer that the world of physical science can be visualized and is an excellent medium for teaching students to model and to picture what happens at the molecular level. The first topic we decided to explore was balancing chemical equations. This seems like such a simple topic to chemistry teachers but I have found that it can be quite challenging for many of my inner city students. The first thing they ask me for is a list of rules that they can follow. We can discuss the problems of algorithmic teaching in a later post! For the time being let’s talk about how to get students to understand why they need to balance equations and discuss what we can call “Conservation of Atoms”.
I recently stumbled across a blog about the use of BCA (Before Change After) tables for stoichiometry written by Lowell Thomson. I was thrilled to discover ChemEd Xchange! I wanted to share my journey, spurred on by my s
Organic chemistry was when I fell in love with chemistry. Also known as Chem 210 at the University of Michigan, it was the first time I actually started to connect what was going on at the nanoscopic level to the macroscopic world. Since then, I’ve been hooked.
Each year we work on specific heat of materials and the heat of fusion of ice. These are two labs that are typical for most chemistry classrooms. Most of the experiments involve a simple calorimetry experiment that uses a styrofoam cup and provides generally good results. There tend to be a couple of key ideas with all of these experiments.
Stoichiometry is arguably one of the most difficult concepts for students to grasp in a general chemistry class. Stoichiometry requires students to synthesize their knowledge of moles, balanced equations and proportional reasoning to describe a process that is too small to see. Many times teachers default to an algorithmic approach to solving stoichiometry problems, which may prevent students from gaining a full conceptual understanding of the reaction they are describing.
This year my students experienced something a little new to them on the Chemistry Olympiad. It was a question about the crystal structure of a mineral. I have not been teaching the “unit cell” concept in great detail and started to reevaluate my unit on liquids and solids. This question has been appearing on the semifinal exam of the Chemistry Olympiad for a few years but not the local exam until this year. I actually like it when something like this happens. It allows me to reevaluate what I am teaching in class, provides me an opportunity to learn new things, and brings new material into my curriculum.