I was to conduct an experiment using hot water and four items I thought to be good insulators. I chose to use a washcloth folded in half, a paper towel folded into a square, tin foil, and a plastic bag. I first placed some water on the stove to get it hot. Then, I added ½ cup of water to each cup. Next, I attached each material I was testing to the top of the cup held on by a rubber band. I then placed ½ cup of water into a separate cup to check the starting water temperature. I predicted that the tin foil would be the best insulator. (See picture below of set up) I based my prediction upon that tin foil was used to keep food items hot after removing from the oven. I also thought that it would be the best because it did not have large air spaces in it. I believed that the tin foil was loose less heat than the other materials I tested, but I was wrong.
After the experiment was set up I began a time span of 30 minutes. The beginning temperature was 147 degrees Fahrenheit. Once my 30 minutes was up, I placed a thermometer into the cup but not removing the material on top. I tried to keep as much heat in before measuring the temperature change. I tested each cup one at a time. After recording my data I concluded that my prediction was wrong. The tin foil was not the best insulator, but the wash cloth folded in half was the best insulator. (See table for all results).
Material on top of cup | Starting Temperature (in degrees Farenheit) | Ending Temperature (in degrees Farenheit) | Total change in temperature (in degrees Farenheit) |
Tin Foil | 147 | 94 | 53 |
Wash Cloth (folded in half) | 147 | 101 | 46 |
Plastic Ziploc Bag | 147 | 89 | 58 |
Paper Towel (folded into a square) | 147 | 99 | 48 |
I believe the type of heat transfer was conduction because the energy was transferred from one molecule to the next. We were testing insulators to see what was able to keep the most heat in.
I did come up with some questions I will test in the future. The wash cloth I tested was thick and had a high thread count. I want to test the different thread counts to see if the cotton is a good conductor of heat. I want to know if the lowest thread count will still be a good conductor or does the thread count even matter. I also want to test the different paper towels. The paper towel I tested was Viva and it was a thick and absorbent. I want to check and see if the quality of the paper towel will affect whether it is a good insulator.
Some other items I would like to test would be hot chocolate, Cheez Wiz melted cheese, oatmeal, and peas. I would also like to check these items in different cups such as a plastic cup, ceramic cup, a Tervis cup, and a styrofoam cup. I would like to know if the cups would play a huge role in the experiement.
This experiment would be hard for me to set up in a Pre-K class. We are using hot materials and the students do not understand heat and temperature. They know when they feel bad they sometimes have a temperature. I have tried to come up with a way to implement this into my class, but have had no luck. I am open for sugestions though :)
If I taught this to my Pre-K students I would like them to learn that temperature is used to measure hot and cold. I would show this by me using a thermometer with different substances. I would talk about how a thermometer worked. then, maybe I can come up with an experiment for them to do based on temperature. The substances I will use will relate to their daily lives such as outside temperature and temperature of milk.

Did you worry that the other mugs were cooling off while you took the first and second temperature? The last one I measured happened to get the coolest.
ReplyDeleteI think if foods were tried the pastas and cheesy foods would hold the most heat. What do you think?
ReplyDeleteYou might consider changing the heat transfer lesson by talking with students about conductors of heat rather than insulators. Students would be able to select material they think might conduct heat from a source. What if you placed a hand warmer between materials and allowed students to feel them? They could predict which materials would transfer the heat and which might not. Do you think your students could understand this concept?
ReplyDeleteKaren,
ReplyDeleteYes I wooried about it. I stated in my paper that next time I would use 4 thermometers in each cup so that their would be less margin for error.
Mcorbin,
I am not sure because I know when I cook mac and cheese the air cools it quickly and then it sticks together. I believe that when it sticks together that it will hold more heat in though....so not sure good question.
Miscienceteacher,
I have never taught this concept to Pre-K. I think a few of the higher students might be able to understand but I am not for sure until I teach a lesson on this. I am thinking about trying a lesson on this sometime in the near future.
How did you get a beginning temperature? I tried and broke the thermometer!
ReplyDeleteDo you live in an area that gets cold? I think even Pre-K students can relate to needing to wear a jacket outside.
Metal is a good conductor of heat. I had the same thought process about foil, but I also used just plastic wrap. Since many of the people around my area use plastic to wrap their windows, I placed my bet on that being the best insulator.
ReplyDelete