Hydrosphere – The sum of all water on a planet.
We finished Module 5 in Physcial Science this week. The students were not too happy with this one. For some reason they believe the study of water to be extremely boring. I mean really, 71 % of the earth’s survice is water and they think it is boring! Well, it is sort of. I tried to make it a little more interesting by adding some excitement.
The first week, we did experiment 5.1 in class: Evaporation, Condensation, and Precipitation. This experiment is trying to evaporate fresh water from salt, but to tell you the truth, it didn’t work so well on our little portable burner. 😦 We were able to get one drop of fresh water, and the student who tasted it said it was salty. I don’t know what happened.
Experiment 5.2; Salt and Ice, was done at home, since we needed a freezer. The students were surprised at how long it did take for the salt water to freeze.
We did experiment 5.3; Cloud Formation, in the classroom. I once again forgot my camera, so I don’t have pictures. The experiment requires warm water, so I filled a pitcher with warm water and sat it on the windowsill until it was time to use. It was so cold in the room, I thought it would cool down too much. Turns out the sun warmed it too much. Once I put the water in the bottles, the bottles fogged up. That isn’t what we wanted. This experiment requires a match be thrown down into the bottle to form smoke, so that the water vapors can cling to the smoke to form a cloud. We had one or two good bottles. So this experiment was a success. Yes, the students lit the matches and had a great time. 🙂 The cloud was formed by adiabatic cooling- the cooling of a gas that happens when the gas expands with no way of getting more energy. Explaining that to the kids was difficult and I still don’t think they understand it.
The students handed in their tests today and I was not surprised to see that it wasn’t their best. There were two questions that were a little confusing and I had to go over those questions. I think we are all glad this module is over with. 😀
Oh, I forgot to mention the extras I did. Since we were studying water sources, I brought in different kinds of water for them to taste the first week. Distilled, spring, well, purified, and city water were tasted. The second week I brought in different sources of survice water. Stagnant water, green pool, creek, and retintion pond water was observed. No, they did not taste it. It was really fun to see the kids facial expressions when I told them their drinking water can be evaporated from these sources. LOL