We are finishing up Module 4 this week. I think the students liked this module better than the last one. The only lab I want to talk about in length this time is the first one. I forgot to take my camera, so I did the experiment again at home. My test tubes were borrowed from my MIL (the one with the portible burner) and they were sticky with tape glue and very yellow. To clean them, I just soaked them in vinegar for a while. They cleaned up real nice!
Experiment 4.1 The Chemical Compositon of Water
What you need:
Make a solution of epsom salt and water in both the jar and the bowl.
Place the test tubes in the bowl; tilting them to let out all the air. You don’t want any air bubbles.
Take you finger and seal the end of the test tubes, while under water.
Take the test tubes and carefully place them in the jar of solution. Do not let go of the test tube until the end is under the water in the jar. Remember you are keeping the air out.
After both tubes are in the jar, place the battery in. Wait a few minutes before placing the test tubes on the terminals. You want all the air to come out of the battery. Notice the white arrow is pointing to a large bubble; that is air coming out of the battery.
Here is a top view of the battery before the tubes are on the terminals.
After a few minutes place the test tubes on the terminals. You do not want to lift the tubes out of the water.
Observe for a while to see what happens. After a while you should have one tube half empty and the other tube 1/4 empty. That didn’t happen in any of the times we tried this. We did get a good amount of hydrogen gas in one tube, but very little oxygen in the other. I was still able to show that there is more hydrogen than oxygen in water. This must happen a lot, because Dr. Wile goes into some detail on experimental error. 😀
If you want to see what else we have done with Exploring Creation with Physical Science, then click on the Physical Science button that the top of the Applie blog. 🙂
Here is fellow homeschooler’s post on this module, I think you will enjoy. Sahm I Am, Wonder’s of Water.