1. Graph the data from Tables 4 and 5 as and send the graph to your instructor. . Points will be deducted for graphs not labeled. Construct your graph on a computer program such as Microsoft Excel®. If you do not have a graphing program installed on your computer, you can access one on the internet via the following links: http://nces.ed.gov/nceskids/createagraph/ or http://www.onlinecharttool.com
2. Calculate the overall temperature change for the cold pack (Tmax – Tmin). Show your work.
3. Calculate the overall temperature change for the hot pack. Show your work.
4. Which pack works by an exothermic process? Use experimental data to support your answer.
5. Which pack works by an endothermic process? Use experimental data to support your answer.
6. Write the balanced reaction between ammonium nitrate and water.
7. Which pack had the greatest change in enthalpy? How do you know?
8. Describe what would happen to the maximum temperature if the experiment used double the amount of hand warmers. Justify your answer.
9. Describe if and how the rate of temperature change would be affected if you crushed the cold pack crystals.
Explain how the law of conservation of energy was observed in this experiment.