Lil' Toasties-
The Chemistry behind hand warmers
Our next project was to create a hand warmer to sell to students at rallies or sports events during the winter months. We also had the option to do hand coolers to use during the summer. This project was based on exothermic and endothermic reactions when salts dissolved in water. Throughout the process of building a hand warmer, we first had to determine what salt we were going to use. To do this, we tested different salts with water and measured their temperature changes. By the end, my group concluded that Calcium Chloride and Sodium Chloride were the best salts to use.
To build the actual hand warmer, we had to test many designs, sizes, and proportions of materials. We had trouble with leakage as well as getting the right salt to water ratio. We tested shapes from hearts to horseshoes (our mascot is a mustang) and hexagons. We also tested hand warmers where the salt was in little vials so you could release it at different times to keep the hand warmer toasty longer. In the end, we came up with a double bagged, penguin duck-tapped, and warmer. The cost with materials is about US$1.25, which is also enough to make a small profit, but our main goal for this project was to better our school community. Overall, this project was definitely one that kept my group thinking. We had a lot of trouble, but came up with a really good potential product at the end of all of our hard work.
We hope to add more improvements because it still has shown some leaking problems in testing. We plant to add more duck tape to make our hand warmers safer and more reliable.
To build the actual hand warmer, we had to test many designs, sizes, and proportions of materials. We had trouble with leakage as well as getting the right salt to water ratio. We tested shapes from hearts to horseshoes (our mascot is a mustang) and hexagons. We also tested hand warmers where the salt was in little vials so you could release it at different times to keep the hand warmer toasty longer. In the end, we came up with a double bagged, penguin duck-tapped, and warmer. The cost with materials is about US$1.25, which is also enough to make a small profit, but our main goal for this project was to better our school community. Overall, this project was definitely one that kept my group thinking. We had a lot of trouble, but came up with a really good potential product at the end of all of our hard work.
We hope to add more improvements because it still has shown some leaking problems in testing. We plant to add more duck tape to make our hand warmers safer and more reliable.
Overall, this project was enjoyable. My group and i delegated the work well and learned by trial and error. If I were to do this project again, I would change our approach. Sometimes we would get frustrated with our design and this would limit our productivity. I learned the importance of keeping calm when your project explodes and how to asses and fix the situation.