A class of 18 students attending the last year of an Italian high school was divided into groups and performed the extraction of pigments contained in hibiscus tea. Each group worked at a different temperature and carried out multiple extractions using distilled water as a solvent. By means of UV-vis spectroscopy it was possible to determine the…

Triboluminescence is a fascinating phenomenon that can engage students' interest in chemistry. However, safe, cost-effective, and accessible laboratory experiments featuring highly triboluminescent substances are limited. To bridge this gap, we present a simple, rapid, semimicro test tube preparation of the visually engaging manganese complex…

Chromatography is a ubiquitous technique in analytical chemistry, and high-performance liquid chromatography (HPLC) is the industry standard for quantitation of components in solution mixtures. However, demonstrating the principles of liquid chromatography to undergraduates via HPLC-based experiments often proves ineffective because of the fully…

Demonstration of a colorimetric approach for nucleic acid detection represents an attractive educational experiment for chemistry undergraduate students in the time of coronavirus pandemic. Herein, a rapid and vivid detection method that visualizes the presence of a specific DNA sequence is described. The plasmon resonance of gold nanoparticles…

Harmful plastic debris found on beaches and in the oceans are not limited to drinking straws or bags. There are several synthetic organic polymers that can be used to make different kinds of plastic materials and have resulted in billions of tons of waste that can reach the aquatic biome and are harmful to freshwater and marine communities as well…

One challenge of teaching chemical analysis is the proliferation of sophisticated, but often impenetrable, instrumentation in the modern laboratory. Complex instruments, and the software that runs them, distance students from the physical and chemical processes that generate the analytical signal. A solution to this challenge is the introduction…

A highly simplified variation on the do-it-yourself spectrophotometer using a smartphone's light sensor as a detector and an app to calculate and display absorbance values was constructed and tested. This simple version requires no need for electronic components or postmeasurement spectral analysis. Calibration graphs constructed from two…

The generation of secondary colors in digital devices by means of the additive red, green, and blue color model (RGB) can be a valuable way to introduce students to the basics of spectroscopy. This work has been focused on the spectral separation of secondary colors of light emitted by a computer screen into red, green, and blue bands, and how the…

The laboratory experiment challenges students to determine 6-propyl-2-thiouracil (PTU) based on Prussian blue complex formation. Prussian blue is formed by ferricyanide and Fe(II) ions which are generated in situ from Fe(III) ions reduced by PTU. The absorbance of this product was measured at a wavelength of 840 nm, after a reaction time of 30…

Mole to gram conversions, density, and percent composition are fundamental concepts in first year chemistry at the high school or undergraduate level; however, students often find it difficult to engage with these concepts. We present a simple laboratory experiment utilizing portable nuclear magnetic resonance spectroscopy (NMR) to determine the…

This paper reports a laboratorial internship included in the Portuguese Science and Technology promotion program "Internships for Young People in Laboratories (Ciência Viva no Laboratório)", which provided high school students an opportunity to approach the reality of scientific and technological research in a higher education…

Graphene's unique combination of exceptional mechanical, electronic, and thermal properties makes this material a promising candidate to enable next-generation technologies in a wide range of fields, including electronics, energy, and medicine. However, educational activities involving graphene have been limited due to the high expense and…

An efficient laboratory experiment has been developed for undergraduate students to conduct hydrogen-deuterium (H-D) exchange of resorcinol by electrophilic aromatic substitution using D[subscript 2]O and a catalytic amount of H[subscript 2]SO[subscript 4]. The resulting labeled product is characterized by [superscript 1]H NMR. Students also…

The flame test is a classical analytical method that is often used to teach students how to identify specific metals. However, some universities in developing countries have difficulties acquiring the sophisticated instrumentation needed to demonstrate how to identify and quantify metals. In this context, a method was developed based on the flame…

Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…