Hand warmer Challenge
HAnd Warmer Challenge
Our Design:
For our design, we decided to use a simple but effective build. We started with a small Ziploc bag full of water that we heat sealed closed, the material of the Ziploc is thin enough where it is easy to break open when needed. We then placed the baggie of water into a larger bag of plastic that contained the ionic salts (Calcium Chloride) and then heat sealed everything inside. The plastic of the outer bag is tougher and more durable than that of the Ziploc so it won't break unless you really force it to.
Our Goal:
Our assignment was to create a hand warmer that increased in temperature by 20 C as quickly as possible and had a volume of around 50 mL, while using cheap, safe, and effective materials along the way. At the end, the goal was to sell the best hand warmer in the student store for winter sports fans. There were many factors that we had to consider during the design process, such as what salt to use, how to properly seal the plastic bags, how to keep the water and salt separate, the size of the hand warmer, and the ratio of salt to water. Before we even started building the prototype, we tested six other salts to discover their ability to hold heat and change temperature. After conducting these tests and recording data, we saw through our results that Calcium Chloride (CaCl2) was the best salt to use.
Reflection:
Overall, I thought that this was a successful project. My group and I worked well together but we had our moments where we accomplished nothing. We got over our problems together the best way possible. Most of the time we all had to come together and share all our ideas to figure out what our next step would be. It was tough getting all of us to focus on the project instead of doing something else. We did a good job preparing but had some trouble pursuing what we wanted. We had to keep trying new things that could possibly work, which was a big theme of this project. Trying and failing made this project very self driven and forced us to learn from mistakes and fix problems that we found. I enjoyed this project but I feel that my group and I could have worked together better to create a better presentation and hand warmer overall.
For our design, we decided to use a simple but effective build. We started with a small Ziploc bag full of water that we heat sealed closed, the material of the Ziploc is thin enough where it is easy to break open when needed. We then placed the baggie of water into a larger bag of plastic that contained the ionic salts (Calcium Chloride) and then heat sealed everything inside. The plastic of the outer bag is tougher and more durable than that of the Ziploc so it won't break unless you really force it to.
Our Goal:
Our assignment was to create a hand warmer that increased in temperature by 20 C as quickly as possible and had a volume of around 50 mL, while using cheap, safe, and effective materials along the way. At the end, the goal was to sell the best hand warmer in the student store for winter sports fans. There were many factors that we had to consider during the design process, such as what salt to use, how to properly seal the plastic bags, how to keep the water and salt separate, the size of the hand warmer, and the ratio of salt to water. Before we even started building the prototype, we tested six other salts to discover their ability to hold heat and change temperature. After conducting these tests and recording data, we saw through our results that Calcium Chloride (CaCl2) was the best salt to use.
Reflection:
Overall, I thought that this was a successful project. My group and I worked well together but we had our moments where we accomplished nothing. We got over our problems together the best way possible. Most of the time we all had to come together and share all our ideas to figure out what our next step would be. It was tough getting all of us to focus on the project instead of doing something else. We did a good job preparing but had some trouble pursuing what we wanted. We had to keep trying new things that could possibly work, which was a big theme of this project. Trying and failing made this project very self driven and forced us to learn from mistakes and fix problems that we found. I enjoyed this project but I feel that my group and I could have worked together better to create a better presentation and hand warmer overall.