atomic structure

An Upcycled Teaching Aid for Ionic Formulas

Determining the empirical formulas of ionic compounds based on charge balance is often a challenge for beginning chemistry students. Many visual aides have been developed for this purpose, from repurposing commercial interlocking bricks to custom 3-D printed bricks. This article describes yet another option– upcycled can carriers.

Analogy Experiment—Projectile Pennies with Rutherford

Atomic theory is a common topic throughout any introductory chemistry course. It is likely that Rutherford’s gold foil experiment gets at least some attention in your course. I have used a simple activity that gives students an opportunity to replicate Rutherford’s experiment through an analogy experiment that may allow for easier conceptualization of the experiment itself and provide additional support for model development.

Chemical Thinking Interactives

As part of a two-week Chemistry Modeling Workshop™ in Houston, TX, I had the opportunity to read the 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.

Figuring Out Electron Configurations

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.

The World's Biggest Flame Test....

Most chemistry teachers I know do flame tests with their students. It ties in well with many topics, is colorful and the kids enjoy seeing the colors and burning stuff. There are many applications. For years I always mentioned that astronomers use the idea of the flame test. They simply look at stars and examine the spectra from the light of these stars. They then match the spectra with the elements and then they can see and infer what elements are millions of light years away. I always mentioned this but never was able to demonstrate it.