Modifications are presented for the iodine clock reaction to introduce the concept of activity and to help students better appreciate molecular aspects of chemical equilibrium. The addition of an unreactive salt affects the activity of the reactants in the iodine clock reaction. The difference in activity affects how long the iodine clock reaction…

A laboratory experiment has been designed for teaching laboratories aimed at training students in the basics of spectroscopy in junior and senior level undergraduate chemistry courses. Despite the ubiquity of light-based tools in modern science, students often find it difficult to comprehend light and light-matter interactions. A portable…

An activity of using waste plastic caps and wooden sticks (or steel wires) to construct crystal structures is described. Caps with different colors represent different atoms/ions/interstices, and sticks are employed to carry the caps and describe the positions of atoms/ions/interstices. The cap-and-stick model clearly demonstrates crystal…

The area of application of electrospray ionization mass spectrometry (ESI-MS), usually coupled with liquid chromatography, seems to be much larger than those of any other ionization method. It gives rise to the demand for new teaching methods that would effectively help students to master the principles of working with and making full use of the…

A chemistry laboratory experiment is described to introduce undergraduate college students to membrane separation technology. This experiment combines a simple nanowire membrane fabrication and visually indicated molecule separation. The membrane is produced via coprecipitation synthesis followed by a filtration assembly process, which can be…

As a widely applied theory that has found success across many fields, density functional theory (DFT) is largely taught. Typically, the most effective way to convey DFT concepts is through illustrative examples that are currently lacking in available resources. In this work, we demonstrate total energy calculations for H[subscript 2] using…

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…

A new teaching resource comprised of raw X-ray diffraction data sets from crystallography experiments has been compiled. The aim of this resource is to provide a tool with which to plug the teaching gap between crystals and chemical structures present at various levels of education, as well as providing examples for early stage researchers and…

Approximations can help to orient the student in an organic chemistry laboratory. There the student needs to develop the solvent systems for the reaction and isolation of organic reactants and products. The adage "like dissolves like" helps in this regard, but this approach is vague and entirely qualitative. More quantitative approaches…

Climate change is a critical scientific and social issue of our time, yet the topic is not frequently discussed by the general public. Additionally, misconceptions about the topic persist. One important aspect of climate change is the greenhouse effect. This activity adds a greenhouse gas discussion to an existing module about molecular shape and…

When structure-property relationships are discussed in inorganic chemistry and materials science, the common perception is that materials with the same composition and atomic arrangement have the same properties. In this laboratory experiment, we show that "processing"--the exact conditions under which materials are made--can in fact…

In this two-session experiment for an organic chemistry lab, students prepare a macrocyclic host compound--namely, a pillar[5]arene--by means of a templated 1,4-dimethoxybenzene/formaldehyde cyclo-oligomerization (session 1), and then, they explore its molecular recognition properties toward the 1,8-diaminooctane guest with the aid of [superscript…

Periodicity in electronic molar entropy values has been shown on the basis of the electronic structures of the elements. Also, with the approximations discussed herein, one can estimate the electronic molar entropy without atomic spectroscopy results. All of this can be accomplished by showing the connection between the vector model of the atom…

The NMR spectrometer is a commonly used spectroscopic instrument that records resonance frequencies of nuclei present in molecular systems. While the NMR frequencies fall within the radio frequency regime for a given molecular system, they are presented in terms of chemical shifts in the audio frequency regime, thereby having the versatility to be…

The COVID-19 pandemic affected a large range of in-person education activities in Colombia. This created great limitations in academic performance for students with reduced access to communication technologies and deepened the educational gaps in the country. This was particularly true for sciences such as biochemistry. In Colombia, molecular…