Thermochemistry to the Rescue: A Novel Calorimetry Experiment for General Chemistry

Abstract

A novel calorimetry experiment that (i) provides “real-world” connections, (ii) assists students in learning thermochemistry, and (iii) uses equipment commonly found in an undergraduate general chemistry laboratory was implemented at our institution. Ultimately, students design a custom heat pack to treat the frostbitten hand of an Alaskan pipeline maintenance worker. First, students measure and use the specific heat of Vienna sausage to approximate the hand’s specific heat. Students obtained a mean specific heat of 3.1 ± 0.5 J g−1 °C−1 for Vienna sausage, which compares favorably with generally accepted values for the human body’s specific heat. Second, students qualitatively determine heats of salt dissolution and identify a salt for their heat pack. Next, students quantitatively determine their chosen salt’s heat of dissolution. Finally, using the Vienna sausage’s specific heat, students estimate the heat required to raise the temperature of the hand from 15 °C (frostbite risk) to 37 °C, calculate the amount of salt and water needed for their heat pack, and fashion and test their heat pack. To gauge student perceptions toward this experiment, a survey was administered. Results indicate that the majority of students enjoyed this experiment (69.3%) and felt that the experiment had “real-world” connections (59.4%).

Designing Calorimeter Made from Various Wastes

“…Alternative materials used as reagent containers in calorimeters are Styrofoam, paper, plastic, melamine, PVC pipe (Polivynil Chloride), and bamboo. These materials are isolators that inhibit heat transfer from the system to the environment or vice versa [25].…”

“…Theoretically, the calorimeter should absorb heat and the value of the resulting heat capacity is positive [8], [9]. Allegedly, this is due to the stirring rotation manually is not constant.…”

Thermochemistry of Acrylamide Polymerization: An Illustration of Auto-acceleration and Gel Effect

“…% (reaction reaches high conversions). Similar assumption to (i) has been used to approximate the heat capacity of human hand using Vienna sausage and coffee cup calorimeter setup [25]. It is worth mentioning that adiabatic calorimetry can be used not only for evaluation of reaction enthalpy, but also, for derivation of kinetic data such as activation energy from the temperature-time dependence relationship [26,27].…”

Discovering the Chemical Mechanism of Common Heating Agents: A Stepwise Inquiry with Student-Designed Experiments in a High School Laboratory Course

“…In the current program, we focused on using the students’ prior knowledge about portable heating packs because these heating packs incorporated different chemical designs, such as those based on the oxidation of iron powder and the reaction between calcium oxide (CaO) and water. They are also familiar household materials, excellent for engaging students during laboratory-based learning programs. − Laboratory-based learning programs focused on the redox reactions occurring in chemical hand warmers via iron oxidation reactions ,, and those which feature the microwave-assisted reduction of the iron oxides in its waste have been reported. A conventional heating pack based on CaO–water reactions was previously used to teach the chemical concepts governing Hess’s law …”