Conclusion
From our results wee can conclude that bubblewrap is the best insulator tested. It took an average of 203 seconds to lose enough heat energy to the atmosphere to reduce the temperature of the water to 70ºC. The cotton material was the least effective insulator - at an average of 169 seconds it took the least time to allow enough heat energy to escape for the water temperature to fall by 10ºC.
These results can be backed up by scientific explanation. Bubblewrap is an effective insulator because each of the bubbles contains air. Air is a very poor conductor of heat because the particles are so spaced out that heat, which is transferred by particles causing bordering particles to vibrate more, cannot transfer quickly through the particles.
Evaluation
Our experiment was not a fair test because different amounts of material were used for each beaker and we attached the material to each beaker differently. These could both be factors which affected our results. However, we did ensure that we started the stopwatch at the same temperature for each test, and that we used the same amount of water for each.
To measure the results, the scientific equipment used included a thermometer and a stopwatch, so except from possible minor timing errors with the stopwatch our experiment was quite accurate.
Our data was fairly valid because we were also using only one independent variable (the material which the beaker was wrapped in), and we did find which was the best insulator, which is the question that we were trying to answer. However, because the experiment was not a fair test we can not say that our results are completely valid.
