A key part of the practice of chemistry is the analysis of chemical composition, including through gravimetric analysis and spectrophotometry. However, the complexity of doing multiple calculations to obtain analytical evidence, such as that required to determine an empirical formula, presents a challenge if such analytical methods are to be…

Techniques and instrumentation that involve fluorescence are used in many careers related to biology and biochemistry. However, due to the expense of instrumentation, the theory and practice of fluorescence spectroscopy is commonly concentrated in instrumental analysis in most curricula, a class rarely required for biology and biochemistry majors.…

Colorful transitions of various acid-base indicators have been used to illustrate the concept of chemical equilibria, especially in spectrophotometric determination of the equilibrium constants or pKa values. To accommodate an online laboratory environment necessitated by the COVID-19 pandemic, this work employs color analyses from digital images…

Optics is one of the subject areas in which students have difficulty learning. Establishing the right connections between the concepts of optics and daily life supports the learning of the concepts of optics. In addition, this connection increases the students' motivation to learn optical issues. In this study, three activities related to prisms…

Circular dichroism (CD) is the differential absorption of left and right circularly polarized light. It arises from molecular electron oscillations that are driven by both the light's electric and magnetic fields, where the effects are in phase for one circular polarization and out of phase for the other. We describe these interactions, which have…

The attractive photophysical properties of luminescent nanoparticles have prompted numerous studies on their synthesis and biological applications. Due to the complexity of components, sizes, morphologies, and strong light scattering of the nanoparticles the absorption spectrum alone is not enough for characterising and analysing the real…

A dual-function student-crafted instrument is described as part of a laboratory activity aimed to teach both the principles and practical aspects of absorption spectroscopy to secondary and introductory undergraduate students. Using minimal changes in an arrangement that is based on interlocking bricks and low-cost components, both a fluorometer…

In order to introduce students to the fascinating field of femtochemistry, we propose here a practical laboratory training course conceived for second-year master's students in chemistry. We describe the use of a broadband femtosecond transient absorption (pump-probe) experiment for monitoring a fast light-triggered chemical reaction in solution.…

A simple diffraction experiment was designed using banana stem as natural grating. Coherent beams of lasers with wavelengths of 632.8 nm and 532 nm that pass through banana stem produce periodic diffraction patterns on a screen. The diffraction experiments were able to measure the distances between the slit of the banana stem, i.e. d = (28.76 ±…

Quantum dots (QDs) are useful for demonstrating the particle-in-a-box (PIB) model utilized in quantum chemistry, and can readily be applied to a discussion of both thermodynamics and kinetics in an undergraduate laboratory setting. Modifications of existing synthetic procedures were used to create QDs of different sizes and compositions (CdS…

Exothermic reactions can present safety hazards and there is a recognized need for reaction safety education at the undergraduate level. We present an experiment that illustrates the pitfall of direct scale-up of an exothermic reaction that can lead to thermal runaway. The iodide-catalyzed hydrogen peroxide decomposition reaction yields…

Without question, one of the most useful tools an astronomer or physicist can employ to study the universe is spectroscopy. However, for students in introductory physics or astronomy classes, spectroscopy is a relatively abstract concept that combines new physics topics such as thermal radiation, atomic physics, and the wave and particle nature of…

Semiconductors are an important class of materials; preparing ZnO nanorods allows semiconducting properties to be easily observed. The week before lab, groups of four students take 15 min to setup two fluorine-doped tin oxide glass (FTO) slides in a zinc nitrate and hexamethylenetetramine solution stored at 90°C until the next lab. Hexagonal ZnO…

A laboratory experiment visually exploring two opposite basic principles of fluorescence of aggregation-caused quenching (ACQ) and aggregation-induced emission (AIE) is demonstrated. The students would prepared two salicylaldehyde-based Schiff bases through a simple one-pot condensation reaction of one equiv of 1,2-diamine with 2 equiv of…

The activity of mushroom tyrosinase can be measured by monitoring the conversion of phenolic compounds into quinone derivatives using spectrophotometry. This article describes a series of experiments which characterize the functional properties of tyrosinase, the analysis of the resulting data using R to determine the kinetic parameters, and the…