If you’ve ever found yourself halfway through a lesson on electron configuration only to be met with blank stares (or that one student who insists on writing ev-er-y-thing in their notes), you’re not alone. The first time I taught it, I felt like I was transported to another dimension. It was straight up miserable for everyone in the room.
Electron configuration is a topic that feels abstract to students—until you put the periodic table in their hands and show them how it’s secretly the answer key. Because the periodic table isn’t just a list of the elements. It’s a map.
Why I teach Electron Configuration with the Periodic Table
Getting my students to actually use the MAP to find their answers makes them better chemists, and gives them the appropriate tools to actually solve their problems. I teach my students how each of the sections of the periodic table corresponds to an electron sublevel. The tall skinny chunk on the left (Groups 1 & 2) is the s-block. The wide chunk on the right (Groups 13-18) is the p-block. The transition metals are the d-block. And the lower piece (the rare earth metals) is the f-block.) From here we can actually SEE the configurations just like a map!
This works best when you’re working with a “proper” periodic table. As far as I’m concerned, the f-block on the bottom, should NOT include lanthanum or actinium. Those should be part of the d-block. If you remember, the s-sublevel holds 2 electrons. That’s why it’s two elements wide on the PT. The p-sublevel holds 6, and therefore is 6 elements wide on the PT. D-sublevel holds 10 – that’s easy. And finally the f-sublevel holds FOURTEEN electrons, and therefore should be 14 elements wide. That means you need to be choosy about which periodic table you print and distribute to your students!
Using the Periodic Table to Determine Configuration
Let’s say you need to know the configuration of phosphorus. It’s in period 3. It’s in the p block. Now you count the depth into the table.
1s² 2s² 2p⁶ 3s² 3p³.
Seriously, take a look at your periodic table. It’s the 5th element in period 3 (add the 2 and 3 of 3s2 and 3p3). Or, as I like to see it, it’s the 3rd element in the p-block. Using my guided notes lesson, this is a breeze! Students aren’t writing too much, or even every little detail. Just the things they really NEED TO KNOW. And the rest of the class time, they are actually watching me go through the process of learning HOW to use the periodic table to guide them. Read more about why I love guided notes in chemistry here.
Bring in the Mystery
Once my students get the hang of it, I like to have them actually practice reading these configurations. (Because practice is where REAL learning happens.) In this mystery activity, students get to think critically and apply what they’ve learned in a super fun and engaging way. Using the mystery, students in your class can be assigned roles to play as “Mystery Kids”. They get a hobby, a birthday, a way of getting home and a picture of “themselves.” Using clues from answering chemistry questions, the students in your class narrow down the list of suspects to uncover the culprit in the Case of the Missing Bike. They can rule out other Mystery Kids until they get down to just one person.
You can have your students role play as Mystery Kids to make it more engaging. But if you don’t have as many students as there are Mystery Kids, it’s not a problem. There’s an easy way to trim it down for smaller classes without issue.
And What if They Need Some Extra Help?
Of course I’m teaching the diagonal rule! It’s pivotal in chemistry. Plus it helps to explain the d-shift (and the f-shift) when you get to the bigger elements. While I use this method as well, it’s not the main point. It’s just an assist. I want my students to know how to read the table, not just memorize the diagonal rule. But of course, the more tools, the better, right? The two together work wonders!
Want to See Where this Fits in Your School Year?
If you’re planning your school year or just want to see where this topic fits into the bigger picture, I’d love to share my free Chemistry Curriculum Outline. It’s part, scope and sequence, part pacing guide, part lab guide, part daily lesson schedule. It’s really everything you need to help you teach chemistry with confidence all year long: Grab the free Chemistry Curriculum Outline here.
