This introductory lesson uses a crosscutting concept, structure and function, as a means to model pre-conceptions of a voltaic cell. A phenomena is used to pique curiosity and engage students as they progress through the unit.
Science Practice: Developing and Using Models
Matt Vonk and Peter Bohacek have just created a handful of new chemistry activities that are based on interactive high-resolution video. These classroom-ready experiments have interactive tools so that students can perform the analysis and record data themselves. In some cases, students can even change variables.
Whether you are looking to add a bit more scientific inquiry to your labs or simply looking for a great stoichiometry lab that can be added to your collection, I encourage you to try something like this with your students!
I will share how I use the Target Inquiry activity, Change You Can Believe In. I have realized that I need to include particulate models within the assessments after the lab to fully evaluate my student's conceptual understanding.
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?
After spending the start of the year using a modified version of the Modeling Instruction curriculum (density and physical properties, followed by gas laws, followed by energy and phase changes), we don’t actually start talking about what’s inside atoms until December. I love that by this point students are already familiar with some of the habits of mind needed to reason abstractly about atoms -- thinking proportionally, explaining macroscopic observations at the particle level -- and we are ready to layer on both more abstraction and the symbolic level. By January, we are ready to explore electron configurations.
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.
This is the first isotope activity I have tried where the students can look inside the model that resembled the atom and find information that reinforced what an isotope actually is. Furthermore, the quantitative data forced them to examine beliefs about different types of averages and what the numbers really mean.
In this blog post, I'll discuss how I've expanded my use of model kits within my chemistry class to help explore a variety of topics with my students.