Hand Warmer Challenge
Presentation:
Our second project this semester was to create a safe, effective, aesthetically-appealing, inexpensive hand warmer to be sold in our San Marin Student Store. With outdoor sporting events in mind, we were tasked with developing such a hand warmer utilizing chemistry.
To begin our project, we touched on the concepts of heat. Using a make-shift calorimeter, we were able to make observations of heat displacement between two liquids when combined. We then expanded our calorimeter experimentation to combinations of various salts and water.
After testing each salt at our disposal, we began to develop a concept for our hand warmer. After a brief period of testing designs, we settled on our idea of a glove with a multi-salt design. Once our idea was solidified, we refined it to the final stage as seen in the presentation.
To begin our project, we touched on the concepts of heat. Using a make-shift calorimeter, we were able to make observations of heat displacement between two liquids when combined. We then expanded our calorimeter experimentation to combinations of various salts and water.
After testing each salt at our disposal, we began to develop a concept for our hand warmer. After a brief period of testing designs, we settled on our idea of a glove with a multi-salt design. Once our idea was solidified, we refined it to the final stage as seen in the presentation.
Concepts:
Heat
q=mcΔt
Endothermic Reactions
Exothermic Reactions
Calorimeter
Specific Heat
- Heat is the energy tranferred between samples of matter due to a temperature differential.
q=mcΔt
- This equation relates energy lost or gained in a reaction to the mass, specific heat and temperature change of a given system.
Endothermic Reactions
- An endothermic reaction is one in which the system gains energy in the form of heat. Simply, the heat of the products is greater than that of the reactants.
Exothermic Reactions
- Conversely, an exothermic reaction is one in which the system loses energy in the form of heat. Simply, the heat of the products is less than that of the reactants.
Calorimeter
- A calorimeter is a device used to measure the heat within a chemical reaction. In our lab, we used a coffee cup and a thermometer to act as a calorimeter to observe temperature changes of various reactions.
Specific Heat
- An object's specific heat capacity is its ability to retain heat. It is defined as the required heat to raise a given mass of a substance by a certain degree amount.
Reflection:
During the course of this project, I had lots of fun, but at the expense of less understanding. Our group was at a disadvantage from the beginning as not a single member was present the first week of the project and due to badly-timed illnesses, our group of three usually was missing a member. If we were to coordinate our ideas in class more, I feel that we could have used our time more efficiently and in turn, made a better product. Another issue was my lack of deep understanding of the subject. Even after completing the project, my conceptual knowledge behind the idea is still relatively minimal. However, this project was still a positive experience as we collaborated well and managed to delegate work without any member becoming overwhelmed. OUr group flowed well and we managed to come up with ideas quickly and execute trials in rapid succession. Part of this was due to our division of labor. Similar to ideas of mass production, we each had designated jobs (bag-cutter, sealer, bag-tier, etc.) which made each task both faster and more high quality. Overall, this project was not the most informative, but I found a new sense of teamwork being established through the process.