Spectroscopy is an integral part of chemical research, and the operation of any spectroscopic instrument is critical in chemical education. This study presents a low-cost, do-it-yourself (DIY) style spectrophotometer system that can be adapted for UV--vis spectrophotometry, fluorimetry, and atomic emission spectroscopy applications. The DIY system…

The dissolution of cobalt­(II) chloride in an appropriate binary alcohol solvent yields an equilibrium mixture, consisting of the differently colored octahedral (pink in color) and tetrahedral (blue in color) cobalt­(II) coordination complexes, which can exhibit a brilliant and reversible pink-to-blue color transition over a ~10 °C window - i.e.,…

This research paper aims to propose a novel didactic sequence inspired by an historical/epistemological study of the evolution of spectroscopy and in particular of colorimetry. The working principles of the historical color comparators and the visual color matching method, first proposed by Duboscq, stimulated us in the development of a five-step…

A simple demonstration adaptable to classroom conditions is presented, which involves the preparation of raffle tickets using filter paper and the solution of selected fluorophores. With an appropriate dilution, the text written on the tickets is not visible to the naked eye; however, it becomes readable once put under a UV lamp. Besides being a…

Blue (B), yellow (Y), red (R), and green (G) color-changing dye was used in a general chemistry course for first-year undergraduate students with nonscience majors to highlight the redox reactions written as the gain and loss of hydrogen. The first experiment is a vibrant color variation using a synthetic dye of indigo carmine. The second…

A new organic chemistry experiment aimed to separate the chlorophyll precursor in plant seeds by column chromatography is described. The primary pedagogical goal in developing this experiment is to establish a simple and interesting chromatographic separation to demonstrate basic concepts and the standard procedure for this important lab…

Thin-layer chromatography, which involves the movement of dyes along a silica-coated plate, is used to observe the progress of chemical reactions and to separate mixtures. We took advantage of this phenomenon to devise a method for generating patterns in the shape of numbers with dots (dot matrix). We prepared the azo dyes necessary for generating…

In the course of combining the Sustainable Development Goals (SDGs) with the science education curriculum, the relevance of the micro- and macroalgae in education is based on the biotechnological future-oriented significance and the ever-growing trend toward plant-based nutrition. So, the micro- and macroalgae are finding their way onto the food…

Undergraduate-level laboratory experiments that integrate multidisciplinary chemistry concepts into a single activity are very appealing and thought-provoking for chemistry students. Here, we use the oscillating chemical reaction to introduce students to the analytical detection concept. The Belousov-Zhabotinsky reaction is employed as a simple…

Red onion, "Allium cepa," juice can dye a cloth sample green upon the addition of alum, aluminum potassium sulfate, and this sample can turn red when subjected to an acidic solution. When the red-colored sample is washed with a neutral or alkaline aqueous solution, its color turns green again. These experiments illustrate color changes…

Raman scattering is a powerful tool for revealing the vibrations of molecules, but as a nonlinear optical phenomenon, its signals can change via mechanisms like resonance enhancement that have no direct analogue in infrared spectroscopy. In this work, complementary measurements conducted on 4-nitrophenol and its conjugate base allow students to…

3D printers have facilitated a wealth of 3D printed molecular models illustrating key structural concepts for student learning. However, general adoption of 3D printed models in the organic chemistry classroom proceeds slowly as the majority of consumer-grade 3D (fused deposition modeling (FDM) and resin) printers are inherently monochromatic,…

Nanochemistry is an important aspect of modern chemical science. Though few educational institutions teach nanochemistry as a formal course, general exposure of students to nanoscience is yet important. Thus, we present a nanochemical activity that could be used as part of many chemistry courses or laboratories based on ChemToy2. This activity is…

An introductory normal phase column chromatography experiment is described and evaluated for second year undergraduate chemistry laboratory class. The experiment involves a nucleophilic substitution yielding a crude mixture of reactant and one product, both of which are brightly colored and contrasting, creating a clearly visual separation when…

Assistive technologies remain important in supporting student learning in both in-person laboratories and the online laboratory environment. In this article, we describe an adaptation of a smartphone technology called the Color Blind Pal app to aid students in complementing online laboratory assignments in a general chemistry course. The app was…