Lesson plan for balancing equations by sulan@dun.org
Teaching balancing equations to high school students is difficult, because often some of the students are still at Piaget’s concrete rather than abstract reasoning stage. That is, they can’t just see the molecules in their head and/or draw them correctly. This lesson plan makes use of an online app (http://www.dun.org/sulan/chembalancer) which makes that abstraction concrete – all of my grade 9 class mastered balancing equations in an hour (including the remedial students) using an early prototype of this app.
Directions:
1. Go to http://www.dun.org/sulan/chembalancer/worksheet.htm. Print out a copy and photocopy as needed for your class.
2. Go down to the computer lab (if you have internet access for all those machines), hand out the worksheet, and have the students play the Chembalancer game at http://www.dun.org/sulan/chembalancer.
3. If you want, you can get the students to show you the http://www.dun.org/sulan/chembalancer/final.htm page when they finish (instead of you having to mark #1-#11 on the worksheet), then initial their worksheet to say they completed the game.
4. Get the students to do #12 and #13 on the back of the worksheet.
Next class, if needed, hand out the traditional paper and pencil equation worksheets, and let them balance the equations without using the computer, to reinforce the concept and for practice.
Here is the answer key for the problems on the worksheet:
1) 1, 1, 1
2) 1, 1, 2
3) 2, 1, 2
4) 1, 2, 2
5) 2, 2, 1
6) 1, 2, 1, 1
7) 1, 2, 1, 2
8) 1, 1, 1, 1
9) 1, 3, 2
10) 4, 3, 2
11) 4, 2, 4, 5
12) 2, 2, 2, 1
13) 1, 2, 1, 2