Hand Warmer Challenge
For this project, our objective was to design and create a hand warmer that efficiently increases in temperature by 20°C, has a volume of about 50mL, costs as little as possible to manufacture, and uses safe and environmentally friendly chemicals. This process involved several labs and tests that resulted in many lapses of trial and error before we reached a successful product. The goal in creating these hand warmers is to hopefully have them available for purchase in our San Marin Student Store for students, faculty members, or even parents. This will help solve the issue of cold hands during winter school days and outdoor athletics.
Chemistry Concepts:
* = how the concept relates to our project
* = how the concept relates to our project
- Thermochemistry - the study of the transfers of energy as heat that accompany chemical reactions and physical changes
- Intermolecular Forces - break bonds and particulate attractions that absorb energy from the surroundings
- Interparticle Forces - form new bonds and particulate attractions that release energy from the surroundings
- Law of Conservation - energy cannot be created or destroyed, only changed from one form to another or transferred from one system to another
- Ionic Solids - are solids composed of oppositely charged ions. They consist of positively charged cations and negatively charged anions
- Extothermic Reactions - a chemical reaction that releases energy
- Endothermic Reactions - reaction in which the system absorbs energy from its surroundings
- Specific Heat - the amount of energy required to raise the temperature of one gram of a substance by 1°C or 1K
- Calorimetry - measurement of the amount of heat released or absorbed in a chemical reaction, change of state, or formation of a solution
- Enthalpy of Formation - the amount of energy released or absorbed during a reaction in which a substance is produced
- Entropy - a measure of the randomness or disorder of a system
Reflection:
Although there were several setbacks throughout this project, it was overall successful because we accomplished our objective while gaining knowledge in thermochemistry and the driving force of reactions. Our group brainstormed well and we settled on a clear idea; however, when it came to the execution of our plan, we found challenges. For one, we had trouble in developing an efficient and accurate way to seal our hand warmer and prevent leaks. After much trial and error, we finally came to the resolution of using a heat sealer to ensure that our edges were fully closed. Secondly, our group had to overcome the hurdle of being without our main material, lithium chloride, for multiple testing days. During this time period we decided to work on perfecting the building process of our model and start creating our presentation. Another conflict we experienced came toward the end where because of multiple absences, we couldn't present our project to the judges. Although this wasn't a major issue, it would have been beneficial to hear the critiques and complements from outside sources regarding our hand wamer. Overall, being part of such a dedicated group that communicated very well with each other is what allowed us to overcome the inevitable issues that occurred.
Throughout the duration of this project I have learned more information and gained new skills. I've come to learn all the following chemistry concepts listed above, formulas for common ions, and how to solve problems involving specific heat, change in temperature, and enthalpies of reaction. I also learned the specific properties of lithium chloride and an overall generalization of exothermic reactions. A few skills that I gained along the way were learning how to use a calorimeter and to how develop a seal with a heat sealer.
With any project, there is always room for further improvement. For me personally, I need to improve on contributing in every aspect of the project instead of focusing on one or two major parts. This will allow for a greater understanding of the full concept, as well as assist my group members even more. Secondly, I want to continue on bettering myself to become more of a leader and to let my voice be heard. These two refinements should make me an even better contributor for my group in future projects.
Recap:
Throughout the duration of this project I have learned more information and gained new skills. I've come to learn all the following chemistry concepts listed above, formulas for common ions, and how to solve problems involving specific heat, change in temperature, and enthalpies of reaction. I also learned the specific properties of lithium chloride and an overall generalization of exothermic reactions. A few skills that I gained along the way were learning how to use a calorimeter and to how develop a seal with a heat sealer.
With any project, there is always room for further improvement. For me personally, I need to improve on contributing in every aspect of the project instead of focusing on one or two major parts. This will allow for a greater understanding of the full concept, as well as assist my group members even more. Secondly, I want to continue on bettering myself to become more of a leader and to let my voice be heard. These two refinements should make me an even better contributor for my group in future projects.
Recap:
2 Peaks: fully completing our designated objective and having strong communication throughout the whole project
2 Pits: failing to accurately seal our bags and lacking the access of lithium chloride for a couple days
2 Pits: failing to accurately seal our bags and lacking the access of lithium chloride for a couple days