Day 72

Now, this was an explosive day for two sections. The O and L sections met in the afternoon. First, we went over homework, talking about balancing equations, telling the difference between synthesis, decomposition, and replacement reactions. We also discussed activation energy and things that speed up and slow down a reaction. This was followed by a short video from unitedstreaming.com that covered all of unit 5.2. We filled out a 10 question quiz while watching the movie, then went over it. Following this, I showed two reactions. The first used potassium dichlorate which was heated in a test tube (a decomposition reaction), releasing oxygen gas. I then dropped a jolly rancher into it and flames shot out. The heat and presence of O2 gas made the reaction take off. This was all done in the fume hood, of course. For the finale, I filled a balloon with H2 gas and put it in the fume hood. Using a long meter stick, I lit the balloon with the window closed and wham! a huge (but safe) bang shook the entire fume hood. This is actually just H2 reacting with the O2 in the air (a synthesis reaction), but it was incredible to watch. I did not assign homework for these two sections, though we will have a quiz on reaction types (Monday for the O's and Tuesday for the L's).

The W and S sections both had a pH lab in the morning, testing 20 different substances with pH paper (1-14) and neutral litmus paper (turns red for acid, blue for base). They were short periods because of our late start, but we got the lab in fine. I did not assign homework from the lab.

Sweet justice.

Day 71

Today, the O section finally got the big bang from creating water that the other sections got yesterday. I told them this was how to make water in the desert--you just need a tank of compressed Oxygen, compressed hydrogen, and some liquid soap solution. Oh, and a match. You don't get much water, but with the big explosion, who cares?

The O, W and L sections learned how to count atoms. Here is a video of my own explanation of how to do this. The sound quality is not very good--I will work on this. For now, though, let's call this an experiment in how it is done. I'll get better at it. Everyone took a quiz over it, and everyone got an A+. How can I be such a great teacher? The answer: I have Mrs. Nolan in my room. She is awesome and was able to troubleshoot areas of weakness for students as we went along. Check out the video if you don't have dialup. If you do, well, as SpongeBob would say, "Good luck with that."


Well, I've tried it myself, and it doesn't work at school. Maybe it will work for you (it does work for me at home, but the sound is awful). I'll keep working on the system. I'm all about customer service.

We got out early today, so the S section sadly missed the lesson for today :( We will make it up tomorrow, assuming we are here. As to getting out early, sweet justice.

Day 70

Thanks to everyone that has posted recently or tried to post. If you are unable to get your post to work, you can always email me directly at jay_lance@L-Spioneers.org . Or you could send in a note with your son or daughter; I'm not picky.

Today was an unusual day with a concert in the morning (which was awesome). During LGI today I finished discussion of my bike trip across the U.S. 16 years ago. I showed slides and told about my adventures. I'm not sure how much of what I said was believed, but it was all true.

In the O section today, we finally made it through both half-groups with the hydrogen bark lab. It is an awesome experience for my students; they become real scientists. Kudos to Cody Wilson and Josh Moyer who prepared over 28 test tubes of hydrogen gas today in only 40 minutes. This was their second time through, and they definitely knew what they were doing.

In the W, L, & S sections today we took our combining atoms quiz, after a complete review. I am proud to say that the average score for the test (in all three sections combined) was 19.8/20! This is what I'm after, and shows that when students spend time studying (even if it is teacher directed studying in class), they can do great things. We used the not-so-smart boards, which helped me to pinpoint weaknesses before the quiz began.

I ended class with trying to blow my hand off, or so it appeared. I did a simple reaction between hydrogen and oxygen to make water, and it is awesome. I put the two gases into a soap solution and made bubbles. I took a handful of bubbles and held it up to a lit Bunsen burner, and then WHAM! they whole school shook. At least I think it did; I had headphones as earmuffs on at the time. My hand survives, I believe, because the process takes gases and turns them into a liquid with a much smaller volume. So the explosion is not heading out, but rapidly collapsing. So far, I've been right. Sweet justice. Oh, and I didn't assign any homework for today, but we are taking another quiz tomorrow on counting atoms. I look for another 100% day.

Day 69

I also offered students the chance to earn some points back on their unit 5.1 quiz--7 points if they can convince a parent/guardian to log onto this site and make a post. My goal is two-fold: one, to let parents know that I am blogging about science class, and two, to reward students for making an extra effort (and to get them looking at the posts as well). I am hopeful that doing this will help parents keep up with our difficult material and help their son or daughter with this great but sometimes difficult subject. Science really is awesome and very important to understand in our rapidly changing world.

I wish that I could take a picture of my fume hood right now to confirm the mess that I made today and yesterday showing what happens when sodium (Na) is put into water (H2O). Sodium is an alkali metal and is very, very reactive, with only one valence electron. When placed in water, it has a greater attraction for oxygen (O) than hydrogen (H), so the water molecule splits and hydrogen gas (H2) is released. The formula for the reaction, which we learned about today in all sections, is Na + H2O --> Na2O + H2 (gas). The activation energy for this reaction is very low, so it doesn't take any additional energy to make it happen. In the L section, I destroyed a test tube for the best demo of the day. In the W section I accidentally set a paper towel on fire, and then a cloth towel (it got hit by sodium, which was wet and still hot--not a good smell). But it all happened in the fume hood, without which I couldn't show this demo at all.

For the WL & S sections today (lesson 5-6), we looked at three EQ's: 5-7: What would be convincing evidence that a chemical change had occurred? Several things, actually. A color change, a precipitate forming, an energy change (exothermic or endothermic), gas given off, and I also added seeing fire and/or smoke. This is not always conclusive proof. Conclusive proof is when a new substance is formed. For EQ 5-8: What is a chemical equation? we looked at the parts of an equation (the left is the reactant side--it reacts; the right is the product side--it is produced). The sodium equation above is a good example. Finally, we looked at how mass is conserved in a chemical reaction (EQ 5-9). Whatever goes in, must come out. We distinguished between an open system that is not contained, and a closed system that is. I showed the disgusting nasty experiments I have hanging on my fume hood--salami, a hot dog, jello, a tomato, and even a pancake. I took a bite out of a nasty rice krispie treat in each section (it was only 8 weeks old--no mold!) and savored the joys of teaching middle school, where nonsense like that still helps students pay attention. I assigned 5-10 and 5-11 for homework.

Here is a video from youtube showing a similar reaction. (This is what makes science fun to learn).

The O section moved on to lesson 5-7. We reviewed combining atoms using the not-so-smart boards (they are small dry erase boards), and then took a quiz on it. Almost everyone got a perfect on the quiz, which made me very happy :) I made sure that we understood it before the quiz, which was a good idea. Somehow this took the whole period, but considering the quiz scores, it was worth it.

And to that I say, sweet justice.

Day 68

This was lab day for the L section. They did an excellent job in the hydrogen lab, first making hydrogen gas and then testing it by placing a lighted splint into a test tube filled with H2. They did an exceptional job cleaning up as well. This lab fell just ahead of our discussion of chemical reactions in class, but we will be discussing them soon. There were three in this lab: putting magnesium into hydrochloric acid, putting calcium into HCl, and finally, setting the H2 gas on fire.

The S and W sections took their quiz on unit 5.1 today (lesson 5-5). This was a difficult quiz on a difficult concept, but they did ok. Five students in the S section actually scored a perfect on the quiz. Way to go! We went over the test in class, as Mrs. Nolan was able to grade the tests for me quickly, record them, and then help me hand them back. Concepts covered on this quiz were covalent bonds, ionic bonds, and metallic bonds. How valence electrons are involved in all types of bonds was also big, as valence electrons (the outer shell electrons), have everything to do with chemical reactions. I also showed a couple of demonstrations--lighting a match (the friction with the box brings about the activation energy needed to light it) and putting magnesium in HCl and water, showing that both produce a chemical reaction. Homework 5-7, 8, 9 was assigned for the next full group.

The O section completed unit 5.6. We went over homework (5-7, 8,9) and I assigned 5-10, 11 for tomorrow. We looked at evidence for chemical changes, chemical equations (what is a reactant and product) and how is mass conserved in a reaction. We talked about open and closed systems and I got share some of the disgusting reactions that are going on in my room all the time (salami in a bag, jello in a bag, a rotten hot-dog in a bag) all of which are closed systems. For the finale today, we put sodium metal into water and watched it react. The second time it exploded and accidentally destroyed a beaker. Whoops!

I can tell that the students have holiday fever. It is tough to focus and study. My hope is that the unit is interesting enough to get them paying attention so that they learn these important concepts.

Sweet justice.