The COVID-19 pandemic, which emerged in early 2020, forced educational institutions in Thailand to chiefly rely on online learning during the government mandated lockdown for almost two academic years. Although migration to the online format seems to suit lectures, it is inadequate for laboratory courses since students could not do the experiment…

A simple inquiry-based activity called "Fruit Puzzle" was designed to investigate high school students' understanding of the relationship between the concepts of density and solution concentration at a submicroscopic level. The first activity allowed students to predict whether five types of fruit would sink or float in water and asked…

A green chemistry experiment is presented for teaching an undergraduate quantitative analysis/analytical chemistry laboratory class through the use of black tea leaf extract for the determination of iron in supplement tablets. Dried tea leaf is a safe, low cost, and widely available source of natural extract that can be used in place of more toxic…

This activity allows students to visualize how to obtain different stoichiometries with various techniques in a single experiment. The involvement of three phases adds to the student's interest. Instructional materials are provided to facilitate the experimental procedures, interpretation of results, and error analysis. The reaction of Li from a…

In this article, a low-cost, simple, and rapid fabrication of paper-based analytical devices (PADs) using a wax screen-printing method is reported here. The acid-base reaction is implemented in the simple PADs to demonstrate to students the chemistry concept of a limiting reagent. When a fixed concentration of base reacts with a gradually…

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…

The blue bottle experiment is a popular chemical demonstration because of its simplicity and visual appeal. Most papers on the topic focus on a new formulation or a new presentation, but only a few discuss pedagogical application for a full lab session. This article describes the use of this experiment in the first session of undergraduate…

This article demonstrates how a student research project could connect classroom and community. Using local citizens' concerns about the adulteration of cosmetics by prohibited substances as a research problem, fifth-year pharmaceutical chemistry students were challenged to use their knowledge to create cost-effective and environmentally friendly…