The Beer-Lambert law is a fundamental relationship in chemistry that helps connect macroscopic experimental observations (i.e., the amount of light exiting a solution sample) to a symbolic model composed of system-level parameters (e.g., concentration values). Despite the wide use of the Beer-Lambert law in the undergraduate chemistry curriculum…

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…

Many students enroll in college general chemistry with an interest in a medical career. In those (and alternative) careers, they will need to make critical decisions about data and how that data are acquired. A significant portion of introductory lab experiments are, in principle, but not necessarily in practice, devoted to understanding how…

A laboratory experiment to determine the concentration of the anti-inflammatory drug ibuprofen in liquid gelatin capsule dosage forms, suitable for undergraduate chemistry or pharmacy students, is described. Either individually, or in small teams, the students digest two 200 mg capsules in a KOH solution. While the capsules are digesting the…

A visual regression analysis using the least absolutes method (LAB) was developed, utilizing an interactive approach of visually minimizing the sum of the absolute deviations (SAB) using a bar graph in Excel; the results agree very well with those obtained from nonvisual LAB using a numerical Solver in Excel. These LAB results were compared with…