A smartphone-based digital imaging method has been successfully introduced in an undergraduate laboratory class to quantify fluoride ions in water. Students first synthesized the chemosensor (E)-2-(1-(6-nitro-2-oxo-2H-chromen-3-yl)ethylidene)-N-phenylhydrazine-1-carbothioamide (CT) via an eco-friendly and green microwave-assisted protocol and…

In this communication, we describe five at-home laboratory experiments and demonstrations that complement a semester-long analytical chemistry curriculum. The experiments were successfully carried out by remote undergraduate students enrolled in a hybrid analytical chemistry course during the COVID-19 pandemic. Students used their personal…

Smartphones, coupled with small mobile sensors, make it possible to work with near-infrared (NIR) spectroscopy in science classrooms. NIR spectroscopy has become a standard analytical technology in various industries. These new devices enable students to create their own data in real time. This article presents an inquiry-based teaching unit, in…

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…

Low cost, open-source analytical instrumentation has the potential to increase educational outcomes for students and enable large-scale citizen science projects. Many of these instruments rely on smartphones to collect the data, mainly because they can effectively leverage a dramatic price-to-performance ratio of the optical sensors. However,…

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…

Routinely used in quantitative determination of various analytes, UV-vis spectroscopy is commonly taught in undergraduate chemistry laboratory courses. Because the technique measures the absorbance of light through the samples, losses from reflection and scattering by large molecules interfere with the measurement. To emphasize the importance of…

Visible absorbance spectroscopy is a widely used tool in chemical, biochemical, and medical laboratories. The theory and methods of absorbance spectroscopy are typically introduced in upper division undergraduate chemistry courses, but could be introduced earlier with the right curriculum and instrumentation. A major challenge in teaching…

Fluorescence quenching is an analytical technique and a common undergraduate laboratory exercise. Unfortunately, a typical quenching experiment requires the use of an expensive fluorometer that measures the relative fluorescence intensity of a single sample in a closed compartment unseen by the experimenter. To overcome these shortcomings, we…

The current model of flipped classroom ensures that learning is not being restricted to the brick and mortar setting. Lessons can be conducted anywhere, anytime, as long as there is a good internet connection. Most of the flipped classroom and e-lectures are videos recording PowerPoint slides with a human voice as the audio instruction. In…

A handheld digital microscope (HDM) interfaced to a computer with a presentation projector is used to project an out-of-focus yellow patch on the screen, then the patch is brought into focus to show that, paradoxically, there are red and green but no yellow pixels. Chromaticity diagrams are used to discuss this observation and spectroscopic…