Evolution and revolution in quantitative analysis

Merging Old and New: An Instrumentation-Based Introductory Analytical Laboratory

“…The changing face of analytical laboratory courses has been the focus of much discussion and debate for more than two decades. − Courses that once emphasized titrimetric and gravimetric determinations of “unknowns” are being replaced by newer pedagogies such as role playing, problem-based learning, − community-based projects, and project-based labs. ,− These new approaches bring an important “real-world” dimension to the course that pushes students toward higher levels of engagement, interest, and ownership in the laboratory experience. Also, as instructors seek to modernize courses by replacing classical wet-lab analysis techniques with modern instrumental methods, the distinction between “quantitative analysis” and “instrumental analysis” becomes harder to discern .…”

Measuring Tablet Dissolution: An Experiment for Teaching Quantitative Ultraviolet Absorption Spectroscopy

“…The purpose of this lab experiment is to use dissolution testing to promote learning important topics in analytical chemistry, including the use of quantitative UV spectroscopy, data handling, calibration, and sampling. 18 ■ EXPERIMENTAL PROCEDURES Chemicals Acetylsalicylic acid (Fisher Scientific; Fair Lawn, NJ) had a crystalline appearance with relatively large rod-shaped crystals having dimensions on the order of ∼0.7 mm in diameter by 1.7 mm long. The crystals were ground with mortar and pestle for 2 min to give the acetylsalicylic acid a powder-like appearance because the rate of dissolution is inversely proportional to particle size of the active pharmaceutical ingredient.…”

“…Furthermore, several articles in the Journal have discussed synthesizing aspirin ( , and analyzing pharmaceutical samples, , but in this experiment students make their own aspirin tablets for subsequent analysis. The purpose of this lab experiment is to use dissolution testing to promote learning important topics in analytical chemistry, including the use of quantitative UV spectroscopy, data handling, calibration, and sampling …”