Recent emphasis on research competencies in undergraduate biology education means that more students are doing course-based research. Professional research scientists learn from failed research, but undergraduate students who encounter failure in their biology lab research may not always respond in ways that advance their learning. There is a need…

In many introductory physics classes, diffraction of light is introduced first, then more advanced diffraction topics such as x-ray diffraction, Bragg's law, and crystallography are covered. Since using x-rays raises safety concerns and atomic spacing in a crystal is not easy to change, microwaves with macroscopic crystals have been used to study…

Chemistry includes observable phenomena and materials related to daily life, but learners sometimes have difficulties understanding the theoretical and abstract nature of chemistry as well as its applications and relating it to everyday experiences. In this manner, the aim of the study is to determine and assess whether pre-service science and…

A student experiment that uses QuEChERS (quick, easy, cheap, effective, rugged, and safe) methodology for extraction and HPLC for quantitative determination of tocopherols from seeds and nuts is described here. Chromatographic separation is achieved by using a pentafluorophenyl stationary phase which gives enhanced separation of the tocopherols…

Oxidation reactions are critical components of the synthetic toolbox taught to undergraduate students during introductory organic chemistry courses. However, the oxidation reactions discussed in the undergraduate curriculum are often outdated as many organic chemistry textbooks emphasize chromium-based oxidants that are no longer in regular use by…

Organic chemistry students often struggle with reaction mechanisms, particularly in how they are proposed and justified. In this activity targeting second year organic undergraduates, students used infrared spectroscopy (IR) to track the reaction progress of two distinct aldol reactions and used polarimetry to analyze the stereoselectivity of…

A laboratory experiment has been devised to train new graduate trainees in the safe and controlled handling of air-sensitive organometallic reagents using Schlenk lines, high vacuum pumps, liquid nitrogen traps, and cannula transfers. The reaction involves the formation of air-, moisture-, and thermally sensitive 2-pyridyllithium, generated in…

Exposure to real-life applications of quantitative analysis techniques based on two gas chromatography (GC) experiments was provided to a large cohort of sophomore-level students. In one experiment, students assessed blood alcohol content by internal standardization using a homemade headspace system similar to methods implemented in forensic…

A well known physics problem is to calculate the friction forces required to support a ladder against a wall. A more tractable problem is to calculate the friction forces needed to support an inclined beam on a ball or a cylinder. In the latter case there are three rather than two points of sliding support. Measurements and calculations are…

The impact force and duration when one billiard ball collides head-on with another is estimated by assuming that the balls are connected by a spring. The results are compared with a measurement when a billiard ball collides with a heavy, rigid surface.

In a traditional teaching approach, a physics course begins with mechanics, and generally the braking effect due to magnetic interactions is not mentioned among the various types of friction presented (static, sliding, rolling) because students will discover magnetism only in later chapters. In our didactic experience this traditional choice is…

The article describes research work that can help students observe and experimentally research the effects caused by the emission component of the filament current in fluorescent lamps' cathodes. When analysing the work of electronic devices--multi-purpose lamps that use thermionic emission--research usually focuses on the current caused by the…

A method is described to measure the coefficient of restitution (COR) by dropping a ball on a piezoelectric disk. Multiple bounces can be observed at small drop heights, so the average COR over say ten bounces can be obtained from just one ball drop, without having to measure the bounce height or the bounce speed. The results show directly that…

A flash purification system using prepacked cartridges containing different silica weights and particle sizes was employed to demonstrate the influence of column characteristics on chromatographic resolution. This chromatographic experiment was a helpful introduction to chromatographic courses where the influence of particle sizes was addressed…

Smartphones and their internal sensors offer new options for an experimental access to teach physics at secondary schools and universities. Especially in the field of mechanics, a number of smartphone-based experiments are known illustrating, e.g., linear and pendulum motions as well as rotational motions using the internal MEMS accelerometer and…