Week 4 - Heat Experiment

For the week four experiment, we had to try to insulate four cups of hot water using four different types of materials. For the materials I chose to test, I looked to things I had around the house: newspaper, brown paper shopping bag, dish towel and aluminum foil. I set up my data table and wrote my predictions about how the materials would insulate, or not the thirty minutes had passed. Then I thought about whether I should boil the water, heat it in the microwave, or run it through the coffee maker. In any of the cases, I knew I’d have to record the temperature at the beginning of the activity. I decided to pass the four cups of water through the coffee maker.

Activity results: excerpt from paper
After heating and pouring the water, I took the baseline temperature of each cup, recording them on my table. The baseline temperature in each cup was 142 degrees Fahrenheit. I covered each cup immediately after taking the temperature to give the insulating material the best chance of retaining the most heat possible from the time the water was poured. Then I played the waiting game. After the prescribed thirty minutes, I uncovered one cup at a time measuring the temperature and then recording each.

As it turns out, the aluminum foil, which was heavy duty foil, made the best insulator as it retained the most heat energy. The closeout temperature of the water was 108 degrees Fahrenheit. The brown paper followed at 99 degrees Fahrenheit. The dish towel was close in third place at 95 degrees. The newspaper had broken apart and the water that remained was close to room temperature as a result. The water vapor rising up out of the cup loosened the fibers of the newspaper and it eventually broke apart.

As I reflect on this activity, I realize that the temperature of the water molecules began to decrease as soon as they left the pot in which they were heated. The water vapor rose upward leaving taking much of the heat energy with it. Further, if I held my had near the cup, I could feel heat radiate away from the cup. In this test, the material that is usually thought of as a conductor of electricity turned out to be the best insulator and retained the most heat energy from the water. However, when I touched the foil, I could feel the heat via conduction. These results would certainly get students to think about the properties of objects a bit more. After my state assessments are over, I plan to do a condensed version of this for my third graders. This will give them something to think about before next year!