Discovering Valence Electrons

Valence electrons dictate the chemical behaviors and properties of elements. After teaching my students Electron Configuration of elements and the relationship to corresponding Bohr models, the students were now ready to learn about valence electrons. I have learned in my 20 years of teaching that the best way for kids to learn is to discover the truths for themselves. When this happens, they are most likely to remember the facts and take ownership of their own learning. This lesson, "where are electrons found", was created and carried out for a formal teaching evaluation of my practice in my classroom. I had taught my students how to write electron configuration and now I wanted them to discover for themselves where valence electrons are found, always, without just telling them directly. Telling them would be fast and allow me to cover more material, but it would not be memorable. After working in groups to create large and colorful displays of assigned family with Bohr models, name of elements, and electron or Nobel gas configurations, students moved in their groups from display to display with the attached sheet to record the highest energy level of the elements in a family and the location of the outermost or valence electrons. By the time they were done going through the wonderful displays that students created, they could conclude for themselves that valence electrons ARE ALWAYS FOUND IN S & P ORBITALS. My principal was blown away by the displays, the activity of students moving as groups from station to station and the post activity discussion. Every child was able to answer the BIG QUESTION: Where are valence electrons found?

This lesson can also be done by just getting students to locate 10 or more elements on the periodic table while not repeating a period or row, writing the electron configuration, boxing in the highest energy level, recording the orbitals found there as well as the number of valence electrons. Here too they will uncover the pattern that valence electrons are only found in s or s & p orbitals. It was a very powerful lesson that can be done in one period after teaching student about electron and noble gas configuration. As a matter of fact, this lesson should directly follow teaching this and can be used as further practice for writing electron configuration.

Another idea is to use the page as an assessment of writing electron configuration, class review of answers, then use the corrected sheet to look for pattern for identifying valence electrons.