The concepts of electronegativity and classical electronegativity scales are briefly described. Electronegativity scales have practical quantitative applications, and this work suggests activities which can assist students select the scales for use in chemistry applications. It provided examples of the use of an appropriate electronegativity…

Bounded by the statements of Feynman and Galileo, I describe certain tricks that can be useful for the teaching of physics. In particular, I describe the calculation of the center of mass (centroid) of an arc of circumference and a circular sector. For this purpose, I also use Pappus's theorems. An Appendix is available with Archimedes' method to…

In this article, we tackle the phenomenon of what seems to be a misunderstanding between science education theory and philosophy of science--one which does not seem to have received any attention in the literature. While there seems to be a consensus within the realm of science education on limiting or altogether denying the explanatory role of…

We describe a simple, intuitively appealing interpretation of the observed ellipsoidal shape of the rotating Earth: it is that surface everywhere perpendicular to the net force upon it.

This work gathers in one place what is pertinent about the connections between metric coefficients, basis- and unit vectors in a four-dimensional relativistic manifold. Some of this material can be found scattered elsewhere; its collection into one place reveals connections that either are not known or are obscure, for example that the metric…

An exciting recent development in chemistry has been the ability to control nanoparticle crystal morphology or shape. Nanoparticles of different shapes present different crystal surfaces (or facets) with respect to the surrounding environment. Synthetic control over nanoparticle morphology has enabled the study of the influence of surface facets…

Reactions between metal carbonates from d[superscript 5] to d[superscript 10] systems and glutamic acid are used to obtain molecular metal complexes and metal-organic frameworks (MOFs). When the ligand is an amino acid, these MOFs belong to the BioMOF class (metal-organic frameworks for biological and medical applications). The metal carbonates of…

Ion transport, involving the diffusion and migration of ions within the electrolyte, stands as a fundamental concept in electrochemistry and serves as the driving force for electrochemical reactions. Electric double layers are critical in the fields of electrochemical energy storage and chemical conversion, constituting a central focus of…

Water is one of the most common molecules in the universe. Water is polarized, but it has many states besides the normal tetrahedron depicted in standard biology texts. Water is also the most ubiquitous molecule on Earth, the universal solvent. It is the internal and external habitat of cells. Ecologically, water is contiguous with life and the…

The mercury beating heart is a classic demonstration to introduce redox reactions in the classroom. Here we report a new, safer demonstration: the Galinstan beating heart. Galinstan is a commercially available eutectic alloy composed of gallium (68.5%), indium (21.5%), and tin (10%) that has low toxicity. When an iron nail touches the Galinstan…

The Wilson cloud chamber is an apparatus used for detecting and observing the trails of alpha/beta rays or even cosmic rays in saturated gas conditions. The principle of this device is based upon the powerful ionization of the aforementioned rays within the medium. This article will provide instruction for creating a classic version of the cloud…

Acceleration of moving objects is usually measured by photoelectric gates. In this paper, a method of acceleration measurement is proposed by pasting white card stock and black tape on a pulley and then using an Arduino to time the motion. This method only needs one photoelectric sensor to measure the acceleration. In contrast, using photoelectric…

Why should our life science colleagues adopt, adapt, and implement fractal thinking into their research and teaching paradigms? While numerous articles and books have been written about the utility, power, and insight that can be gained by using fractal analysis of data and developing fractal models, other than just appreciating the beauty of…

Thermal cameras have shown to have utility in secondary school classrooms and undergraduate courses. In this paper, the author argues for their potential in the primary school classroom and presents a range of activities that can be undertaken with thermal cameras (or supplied images). With limited access in mind, the activities in this paper have…

After a time away from the classrooms and laboratories due to the global pandemic, the return to teaching activities during the semester represented a challenge to both teachers and students. Our particular situation in a Microbial Physiology course was the necessity of imparting in shorter time, laboratory practices that usually take longer. This…