Blogs

Figuring Out Electron Configurations

connecting ionization energy to 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.

LED lights and the Periodic Table

Every LED light has a "band gap". Electrons are pushed into an empty orbital which is negative and then the positive end of the circuit attracts the electrons. As they go down in energy through the band gap, they emit light. The larger the band gap, the more energy, the smaller the wavelength and the closer to the "blue" end of the spectrum. So, the key is to try to control the band gap and thus control the color of light. 

Beyond the Curriculum

I always find this time of year quite harrowing. I am right in the middle of academic competition season with Olympiads in physics, chemistry, biology, and math. I have science bowl and ocean bowl along with bridge building all on the same day. Why do we do this to ourselves?

Ionic Covalent Compounds and Card Sorts

Ionic Covalent Card sort

Card sorts are a great way to achieve a number of classroom objectives.  They can be used as a review activity or they can be done during the middle of a lesson as a type of formative assessment. Sorts can encourage students to work with other students or can even be used as a type of exit ticket. I decided to use the strategy about two thirds of the way through a unit on covalent and ionic compounds and lewis structures. I knew there were items we did not cover in the sort but I was curious to see how they would approach these unknown topics.