I was frustrated today in the S section. Just as we got to the end of the lesson, my camera failed to work and I ran out of time trying to fix it. Consequently, they did not get to see the potassium dichlorate decomposition reaction, nor the hydrogen and oxygen synthesis reaction with the balloon full of hydrogen. I was already working from behind with them because I lost one period with them last week. Oh well! We'll do it tomorrow. If you have an old video camera at home that you don't use anymore, but it still shows an image, and you'd be willing to donate it to the school, please let me know. I think this one is close to being done.
The S section made it through two lessons in one day, more or less. We took our counting atoms quiz first (they did awesome) and then watched the United Streaming video on chemical reactions with a worksheet quiz they filled out. After this, I planned on showing the demonstrations, but alas no time.
The W section went over the rest of the homework for Unit 5.2, which covered ways to speed up reactions (increase surface area, heat up the substance, and increase the concentration of any liquids) as well as what activation energy is (the minimum amount of energy required to start a chemical reaction). I showed them the two demos mentioned above that the S section did not see. The balloon exploding was awesome, as always.
The L section completed the pH lab. They tested 20 different substances to determine their pH and whether they were an acid or a base (or neutral). They did very well. There is an excellent tutorial in this on explorelearning.com (the link is to the right on this page). Go to your homepage there and click on pH analysis. It is self-explanatory.
The O section learned to tell the difference between three reaction types: synthesis (A + B --> AB), decomposition (AB --> A + B) and replacement (AB + C --> BC + A). We mastered it in class then took a quiz to make sure we had it. They did excellent. The couple of students who did not do as well will retake the quiz to make sure they understand. I will give them their better score. At the end of class I showed a short demonstration of a decomposition reaction with ammonium dichlorate. It looks like a small volcano. We talked about the various evidence to support the conclusion that this was a chemical change.
Sweet justice!
