Zinc oxide is a common additive in food, cosmetics, and medicines. Here, we describe the validation of methods to analyze two pharmaceutical samples containing ZnO--talc powder and dermal ointment--by ethylenediaminetetraacetic acid (EDTA) titration. The methods developed were implemented as a practical class to students of a Quantitative Analysis…

This paper presents an experimental lab designed for undergraduate students which focuses on soil science and chemistry. Students perform a series of tests to classify soil's phosphate retaining characteristics, texture, pH, organic matter content, and permeability with the addition of a novel soil amendment, Al Mg biochar. This lab has minimal…

Despite efforts to help youth form better connections to the natural world, many recent science initiatives (such as the "Next Generation Science Standards") privilege laboratory science over field science, thus reinforcing an image of science that is placeless and individual. To better understand the impact of field science on youth, we…

There is a large variety of goals instructors have for laboratory courses, with different courses focusing on different subsets of goals. An often implicit, but crucial, goal is to develop students' attitudes, views, and expectations about experimental physics to align with practicing experimental physicists. The assessment of laboratory courses…

The Crookes radiometer (also known as a light mill) is a fascinating sunlight-powered device, in which a set of vanes is placed inside a glass bulb within which a partial vacuum has been pulled. The vanes then rotate when sunlight shines on the bulb. The reason for the turning of the vanes was subject to intense debate and many students still have…

The article describes a methodology for studying Fresnel diffraction with the active involvement of students in discussing the results of a demonstration experiment. To create a clearly visible model of Fresnel zones, a centimeter radio wave range was chosen, in which the first zone is about 10 cm in size. This makes visible the created…

E-learning is not a new concept to the American University of Nigeria (AUN); however, it has always been applied to the lectures but not in the laboratories for the chemistry courses before and during the first phase of the COVID-19 lockdown. The sudden disruption of learning caused by the forced lockdown issued by the government authority in an…

This work describes the design and testing of a low-cost light-emitting diode (LED)-based nephelometer for turbidity analysis. It also describes the use of this nephelometer for context-based learning (CBL) experiments designed for teaching laboratories. The LED nephelometer is simple, low-cost, and robust, providing similar results as a…

Successful demonstration of lipid assembly chemistry to a general audience can be challenging on both physical (nanoscopic dimensions of lipid assemblies) and intellectual (complex, interconnected concepts) accounts. Quite often, an instructor has to leave key concepts out of what is being offered due to time constraints, which unfortunately…

Virtual chemistry laboratory modules were investigated as a potential learning resource that complements traditional in-person experiments. In collaboration with a high school instructor, we designed two interactive modules, "Rates of Reaction" and "Models of Organic Molecules," which became part of a previously reported online…

A loop-the-loop experiment is described to show how sliding friction affects motion of the ball. Conservation of energy can be used to explain the basic physics, but significant energy loss is observed in practice and expands the usefulness of this apparatus as a teaching tool.

A loop-the-loop experiment usually involves a ball rolling around a vertical loop. A different version of the experiment is described where a nut was allowed to slide around a vertical loop. In both experiments there is a large decrease in kinetic energy when the ball or the nut first enters the loop.

For single-slit diffraction and double-slit interference experiments, commercially made slits can be the most expensive parts, especially since the prices of laser pointers have become very low. One option is to use a razor blade to cut slits in either paint or electrical tape on microscope slides. However, this takes practice, and there is some…

Laboratory astrophysics and astrochemistry are emerging fields highlighting the importance of laboratory simulations and experiments to benefit remote observations. In particular, ice mixtures found in the outer solar system may offer insight into the early evolution of organic molecules. H[subscript 2]O-ice mixtures containing other species such…

Student misconceptions of the double-slit experiment (Fig. 1) are abundant. The most common ones that we observe include: (1) belief that constructive interference requires both pathlengths to be integer multiples of the wavelength ("L[subscript 1] = n[subscript 1][lambda]" and "L[subscript 2] = n[subscript 2][lambda]") rather…