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.
