ELA Component

The project I chose investigates the effect of temperature on the crystal formation of sodium acetate in handwarmers. When I was in second grade, my mother’s colleague had hand warmers, and when he showed me them, I was amazed. To someone so young, handwarmers were extremely fascinating and seemed almost magical. The idea that a small little pouch could generate so much heat in the pocket of my sweater was overwhelmingly cool. To this day, I was amazed my hand warmers. When I was searching for a project to perform, I stumbled upon this one--my perfect match.

To conduct this experiment, I created water baths of 40, 20, and 0 degrees C. In each bath, I placed a hand warmer, ensuring that it is both covered completely and that the bath remains the same temperature the entire time. I allowed the hand warmer to stay in the water for 5 minutes. When the time was up, I took the hand warmer out of the water, shook it vigorously for about 10 seconds, then placed it on a plate and cut it open. I observed the sodium acetate reacting in the hand warmer, and recorded the temperature of it every minute for 15 minutes.

In the 20 degree bath, the temperature increased by only one or so degrees until the fourth minute, when it suddenly increased by 8 degrees. From there, it steadily increased by about 2 degrees per minute. In the 40 degree bath, the temperature change was most constant, changing by 2-3 degrees every minute. Finally, in the 0 degree bath, the temperature increased the most as well as the fastest, starting at 17 degrees at minute 1 and making it all the way to 62 degrees by minute 15. Thus, the 0 degree bath caused the handwarmer to work the most effectively.

How well sodium acetate reacts depends primarily on temperature. Knowing the temperature at which it reacts best (in this case, 0 degrees C) can help to ensure it’s most efficient reactivity when used in products. Sodium acetate can be used for a variety of things, including in the textile industry, in concrete, and, believe it or not, in food as a seasoning. In fact, sodium acetate can be found in most salt and vinegar potato chips, as well as in heating pads or hand warmers.

The purpose of the PBL assignments is to allow us, as students, to research and invest time into a topic that interests us, rather than having a random project assigned to us. This experience has not only allowed me to investigate something I was curious about, but it allowed my knowledge of scientific principles to grow. Overall, my experience with PBL has been extremely educational and enlightening.