Monthly Archives: December 2014

Final Lab Reflection

Background of our experiment

My group members, Bryan Vermes, Jessica Hickey, and I designed an experiment for our final project on temperature and heating. We focused on insulation effectiveness (R-value) and Heat Capacity (H). The purpose of this lab was to explore the relationship between different insulating materials and heat containment. The lab highlights the impact of specific heat figures and the amount of heat requited to raise temperature.

The experiment we put together used water as the constant liquid heated to explore insulation effectiveness. We designed this part of the lab to have four different types of insulation materials: cotton, wool, aluminum, and plastic. We wrapped each material once around a paper cup and used extra material to cover the cup when needed. Each cup would obtain the same amount of water and would be heated to 80 degrees Fahrenheit. Once the water reached this temperature, it would be distributed evenly into each of the four cups, covered with the specific material, and left to sit for 10 minutes. After the time is up, the temperature would be measured again and the R value would be calculated using the formula:  change in temperature / the amount of temperature change per unit of time.

The second part of our lab was designed essentially the same way, but exploring the impact of the specific heat value of different liquids. We designed this lab to include milk,  vegetable oil, and water using cups wrapped with aluminum foil. After the steps above were repeated and finished, heat energy was calculated. In order to do we used the equation: H= (M)(C)(change in T)

Results in the Lab

Once our lab was performed, we collected the following data:

Part 1:

Cotton- start temp: 80 degrees F, end temp: 68 degrees F, R Value: 1.2

Plastic- start temp: 80 degrees F, end temp: 68 degrees F, R Value: 1.2

Aluminum- start temp:80 degrees F, end temp: 66 degrees F, R Value: 1.4

Wool- start temp: 80 degrees F, end temp: 53 degrees F, R Value: 2.7

According to this data plastic and cotton insulated the best, followed by aluminum, then wool.

Although this data does not yield results supporting our original hypothesis (aluminum and wool would insulate the best) it shows that insulating materials do matter in heat sustainability.

Some improvements that I believe would help yield more valid and reliable data would to have 4 thermometers instead of 2. If we had four, we would have been able to measure the liquids both as they were heating up and as we were measuring the final temperature after the 10 minutes, all at once,  instead of having to wait to measure one at a time. Because we only have two thermometers some of the water was left on the hot plate longer than others, so some may have been measured incorrectly. Also, when the time was up to measure all four of the cups after 10 minutes, the group had to measure each cups temperature one at a time, which could have led some of the other cups to cool down; making our data invalid. Next time, I would probably either have 4 thermometers or stagger the time so you can measure all the cups at once right as the time was up.

Part 2:

Water- temp start: 80 degrees F, end temp: 70 degrees, heat energy: 10

Milk- temp start: 80 degrees F, end temp: 66 degrees F, heat energy: 12.6

Vegetable oil- temp start: 80 degrees F, end temp: 57 degrees F, heat energy: 11.09

According to this data, Water held its heat the best followed by milk, then vegetable oil.

As you can see, water in aluminum during this part of the lab already shows that aluminum is a better insulator than any of the above insulation materials. Besides that, I think this part yields valid data. There was one less cup to measure, and during this part, the oil reached 80 degrees F first, so there were three different timers going on. Since the time was staggered, the measurements of temperature change were more accurate.

Reflection

Overall, I think this lab experience went very well. Bryan, Jessica and I split up the work and all bought different materials needed for the lab. We worked well together and found time outside of class to talk and prepare our materials before the experiment.

The lab itself utilized more time than we originally thought, which only allowed our experiment to be performed once during the lab time. The liquids took longer to heat up than we expected and we could only fit so many cups on the hot plate. Maybe if we had another hot plate and more equipment, the lab would have went by faster. There was a lot of sitting and waiting, but that is just a part of science!

I enjoyed this experience and enjoyed performing our classmates experience, I learned a lot in this class this semester!