Recent progress in elucidating chemical reactions allows to explain chemistry by the potential energy of the involved chemical structures. Nevertheless, from an educational point of view, empirical results indicate that students often do not connect the core idea of energy with other chemical concepts. From a resource-oriented perspective,…

Molecules and Computer: Chemistry Calculations in Class (MC[superscript 4]) is a computational laboratory intended for final-year high school or undergraduate students. The topic is the antioxidant potential of anthocyanidins, which is chemically related to their radical scavenging action via the mechanism of hydrogen atom transfer (HAT). This…

The contemporary Human activity utilizes huge volumes of digital data to solve efficiently multiple socio-economic, scientific and technical problems. Now the big data analysis is mainly oriented to the socioeconomic sphere with a goal to lift the profit. The science and technology to penetrate deeper in the nature of objects and systems under…

Activation energies form an energy barrier to a chemical reaction taking place. Simple collision theory, i.e. that particles need to collide to react, would suggest that activation energy is the energy needed to overcome a coulombic barrier provided by the negatively charged electrons contained within energy shells surrounding an atomic nucleus.…

Misconceptions are the "the old, the bad, and the ugly" prior knowledge, ideas or conceptions that the learners have that hinder their further learning in science. Several types of misconceptions that undergraduate students hold about reaction coordinate diagrams (from here on we use the term "reaction coordinate diagrams" and…

Jensen's scheme for the logical structure of chemistry is taken as reference to study the logical structure of physical chemistry. The scheme distinguishes three dimensions (composition and structure, energy, and time), with each dimension treated at one of the three levels (molar, molecular, and electrical). Such a structure places the outer…

The thermodynamic criteria for spontaneity and equilibrium in multireaction systems are developed and discussed. When N reactions are occurring simultaneously, it is shown that G and A will depend upon N independent reaction coordinates, ?a (a = 1,2, ..., N), in addition to T and p for G or T and V for A. The general criteria for spontaneity and…

In this study, we investigated students' understanding of concepts related to the microscopic model of gas. We thoroughly reviewed the relevant literature and conducted think alouds with students by asking them to answer open-ended questions about the kinetic molecular theory of gases. Thereafter, we transformed the open-ended questions into…

Additive manufacturing, commonly known as 3D printing, is gaining popularity in a variety of applications and has recently become routinely available. Today, 3D printing services are not only found in engineering design labs and through online companies, but also in university libraries offering student access. In addition, affordable options for…

Thermodynamics, and in particular entropy, has been found to be challenging for students, not least due to its abstract character. Comparisons with more familiar and concrete domains, by means of analogy and metaphor, are commonly used in thermodynamics teaching, in particular the metaphor "entropy is disorder." However, this particular…

An experiment is described that determines the activation energy (E[subscript a]) of the iodide-catalyzed decomposition reaction of hydrogen peroxide in a much more efficient manner than previously reported in the literature. Hydrogen peroxide, spontaneously or with a catalyst, decomposes to oxygen and water. Because the decomposition reaction is…

An upper-division undergraduate chemistry experiment is described which utilizes DigiSim software to simulate cyclic voltammetry (CV). Four mechanisms were studied: a reversible electron transfer with no subsequent or proceeding chemical reactions, a reversible electron transfer followed by a reversible chemical reaction, a reversible chemical…

A simple and fast experimental method of determining absolute zero temperature is presented. Air gas thermometer coupled with pressure sensor and data acquisition system COACH is applied in a wide range of temperature. By constructing a pressure vs temperature plot for air under constant volume it is possible to obtain--by extrapolation to zero…

In this article we discuss the concept of equilibrium establishment in four most usual instances as is electrostriction and vaporization as related to the concept of equilibrium shell formation. Two more cases are then studied which are of relevance. One is the Brownian movement, the study of which is essential for pedagogical reasons as to…

A laboratory inquiry into the thermochemical relationships in the reaction between aqueous solutions of NaHCO[subscript 3] and NaOH is described. The enthalpy change for this reaction, delta[subscript r]H, and that for neutralization of strong acid and NaOH(aq), delta[subscript n]H, are determined calorimetrically; the explanation for the…