The design and operation of the vapor-absorption refrigerator (VAR) are described using the principles and tools typically covered in upper-division undergraduate physical chemistry courses. The objective is to enable students to understand in detail how this device works and how it compares with more typical vapor-compression refrigerators.…

A spreadsheet-based exercise for students is described in which they are challenged to explain and reproduce the disparate temperature dependencies of the heat capacities of gaseous F[subscript 2] and N[subscript 2]. For F[subscript 2], C[subscript p,m] increases from 300 K, reaches a maximum at 2200 K, and then decreases to 74% of the maximum…

A newly developed laboratory learning program for high school chemistry courses is discussed, in which students discover the chemical mechanism governing exothermic phenomena during the reaction between a heating agent, namely, calcium oxide (CaO)--aluminum (Al) mixture, and water. Based on prior knowledge of simple heating agents such as CaO, the…

This study focuses on designing a laboratory learning program for a high school chemistry course in which students could discover the fundamental principles of Hess's law via stepwise inquiry. By exploring the chemical properties of common desiccants, mainly those that were reactive in water, students were introduced to the exothermic reaction of…

Connecting the thermodynamic definition of entropy, dS = dQ/T (Clausius's equation), with the statistical definition, S = k[subscript B] ln [omega] (Boltzmann's equation), has been a persistent challenge in chemical education at the undergraduate level. Not meeting this challenge results in students taking away the meaning of entropy in a vague…

Infrared (IR) thermography renders invisible infrared radiation with intuitive coloration in images and videos taken of objects, reactions, and processes. Educators can take advantage of this technology to extend students' sensory perception of chemical reactions or processes that absorb or release heat in rich detail. In theory, IR thermography…

Although students take courses in transport phenomena and thermodynamics, they probably do not ask whether these two subjects are related. Here we give an answer to that question. Specifically we give relationships between the equations of change for total energy, internal energy, and entropy of transport phenomena and key equations of equilibrium…

A low-cost alternative to the typical scientific laboratory water bath or a hot plate stirrer water bath is proposed. Readily available immersion circulators have been developed for sous vide cooking. These precision cookers are designed to maintain water at an exact temperature and thus are well-suited for the similar laboratory requirements of a…

The cannon boring experiment of Count Rumford, where eight kilograms of water were boiled by metal on metal friction, is investigated. Consideration of this dramatic demonstration can enrich classroom discussions of calorimetry, units of measure, elements, and thermodynamics. A section pertaining to use of the article in the classroom appears…

Thermogravimetry coupled with Fourier transform infrared spectroscopy (TG-FTIR) is a useful technique for the thermal and structural characterization of materials at academic and research levels. This paper describes an experiment for chemistry students to understand the use of TG-FTIR for advanced qualitative and quantitative thermal analysis…

The strongly exothermic nature of reactions between molecular oxygen and all organic molecules as well as many other substances is explained in simple, general terms. The double bond in O[subscript 2] is much weaker than other double bonds or pairs of single bonds, and therefore the formation of the stronger bonds in CO[subscript 2] and…

Lab activities typically involve phenomena that are invisible to the naked eye. For example, in thermodynamics transfer of heat and temperature changes are perceived by the sense of touch or indirectly observed by the use of thermometers. New tools can be introduced to increase the opportunities for talking science. In this paper, we explore…

The most important indicator of meaningful learning in science education is that the students learn and often encounter in their daily life in the description. To be able to implement this, students need to be a good science literate. This study was carried out in order to reveal to what extent the teacher candidates can explain the relationship…

In the case of Chemistry subjects at the higher middle level, students tend to have a low performance in terms of academic exploration, either because of lack of motivation or lack of preparation in previous courses. In order to improve not only the academic performance of students in some topics of thermodynamics, but also the quality of…

Considering the relevance of thermodynamics to the scientific discipline of chemistry and the curriculum of the Western school system, the philosophical system of Mario Bunge, particularly his ontology and epistemology, is used herein to analyze the presentation of the first law of thermodynamics in 15 school and university textbooks. The…