When describing abstract concepts like chemical bonding, it always seems to feel far too easy for both teachers and students to resort to the “wants” and “needs” of atoms. After all, we understand what it means to want, need, or like something, so it often feels appropriate (and easier) to use a relatable metaphor or subtly anthropomorphize these atoms to accommodate our students’ current reasoning abilities. While predicting the types of bonds that will form and the general idea behind how atoms bond can be answered correctly using such relatable phrases or ideas, the elephant in the room still in remains—do our students really understand why these atoms bond?
A few months ago I was searching the internet, looking for a better way to teach stoichiometry to my pre-AP chemistry students. While my methods of dimensional analysis “got the job done” for most students, I would still always lose students and many lacked true understanding of what was happening in the reaction. I wanted to try something new that would promote a better chemical understanding. In my search for this elusive stoichiometry method, I came across Dena Leggett’s ChemEd X blog post entitled “Doc Save Everyone”, as well as other posts about BCA tables from Lauren Stewart, Lowell Thomson, and Larry Dukerich.
In an effort to better understand my high school students' knowledge of what is happening during phase changes, heating curve calculations, and the ever popular can crush demo, I run them through a series of activities. First, I ask my students "What Temperature Does Water Boil At?"
Students will build models of isomers while the instructor walks around from station to station to critique the models. If the model is incorrect, the students rebuild until they get it right. The paper that accompanies this assignment is very easy to grade.
In this "Pick" I'll briefly describe how I use the ChemDraw iPad App for creating structures for my teaching. I also provide a link to a tutorial where I share some tips on how to get started using ChemDraw on your iPad.
Atomsmith works really well on Chromebooks and other platforms. Students can manipulate molecules, add water, do experiments, heat solutions and examine intermolecular forces all on the particulate level. Another nice feature is the "Experiment" section. There are a number of guided activities, usually never more than a page or two. I have found them to be great supplements for activities, experiments and demonstrations.
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.
It was the empty terrible feeling in the pit of my stomach at 9:30 at night that really bothered me as I am wading through the stack of papers that I was grading. I had the students do experiments, worksheets, I lectured and there was homework. Some of the students could “do” what I thought was science. They could calculate the answer. They could balance the equation.
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.