For this project, our groups were assigned to make the most efficient hand warmer. Our prototype was required to increase in temperature by 20 degrees Celsius, while being cost efficient and safe. Before beginning the project, we created a list of unanswered questions to investigate:
What type of salt should we use? How big can the hand warmer be? How much of the salt should we use? What is the cost of producing these hand warmer? Is the profit worth the manufacturing process? What chemistry process are used? How can we manipulate the hand warmer to increase by 20 degrees Celsius? Are there any safety precautions?
To produce our hand warmer, we tested different types of salt their influence on the change of temperature. From our date we concluded that calcium chloride was the most efficient. We also calculated the solution's enthalpy, the calorimeter constant, how much energy was lost, and how much calcium chloride we needed in grams. These calculations, in addition with background information, data tables, design of the prototype, and cost analysis, can be found in the presentation below.
Reflection
This project was very interesting and took lots of hard work. We had good ideas and executed the our presentation very well. One part of the project that we struggled with was collaboration. I found myself doing most of the calculations and presentation. I think next time there should be more communication between group members on each person's responsibilities. Another thing we could improve on is staying on task. We often found ourselves getting distracted and wasting time on irrelevant things. Although we had a few weaknesses we also had strong positives. I think that our definite strength is our presentation. Even though we had only practiced a few times, our presentation wen very smoothly and overall we accomplished what we needed to do.