Photogates play an important part of many of today's physics laboratory experiments. They signal when an infrared (IR) beam is interrupted, thus supplying the experimenter with important timing information. Currently photogates use an infrared photodiode (IR transmitter) and a phototransistor (IR receiver). User-built photogates have a weakness…

The Folch method is a commonly employed, simple biochemical procedure used to extract fat from food items and biological samples in biochemistry laboratories. The iodine number of fat reflects its degree of unsaturation. In the present study, the iodine number of fat extracted using the Folch method from cow milk, goat milk, chicken egg yolk and…

The subject of pharmaceutical research has traditionally focused on drugs with systemic effects. However, contemporary approaches aspire to achieve targeted drug delivery, with the aim of combatting infections with a precise immune response. Active substances are encapsulated in nanoparticles, transported through the body, and selectively released…

This article reviews the origins and use of the terms quasi-experiment and natural experiment. It demonstrates how the terms conflate whether variation in the independent variable of interest falls short of random with whether researchers find, rather than intervene to create, that variation. Using the lens of assignment--the process driving…

A laboratory experiment has been designed for teaching laboratories aimed at training students in the basics of spectroscopy in junior and senior level undergraduate chemistry courses. Despite the ubiquity of light-based tools in modern science, students often find it difficult to comprehend light and light-matter interactions. A portable…

[This paper is part of the Focused Collection on Instructional labs: Improving traditions and new directions.] In this paper, we describe the results of a research project whose goals were to (1) develop and implement video-based experimental investigations using the Investigative Science Learning Environment (ISLE) approach and (2) study how…

This report describes a laboratory experiment for an undergraduate-level inorganic chemistry or biochemistry course involving the study of the kinetics of the catecholase activity of a synthetic nickel­(II)-oximate complex. A model substrate, 3,5-di-tert-butylcatechol(DBC), undergoes aerobic oxidation to 3,5-di-tert-butylbenzoquinone (DBQ) in the…

Poinsettia ("Euphorbia pulcherrima") contains anthocyanins that dissolve in water and exhibit color changes due to changing pH. This property makes the poinsettia extract a useful acid-base indicator for pH demonstrations. When combined with common household materials, this experiment can be used as an alternative low-cost tool in…

MóviLab (Moving Lab) was an educational strategy developed at Universidad Industrial de Santander, Colombia, to promote chemistry and science among schoolchildren and teenagers from far rural areas of the Santurbán moor in Colombia during the COVID-19 pandemic. The strategy consisted of designing a kit with chemistry experiments that could be done…

Herein, two simulated electrochemistry experiments, namely, the (i) electrochemical series, using an electronic half-cell module, and (ii) citrus fruit battery series are demonstrated for undergraduate chemistry students. The demonstration can be performed for in-person and remote students by connecting the electronic half-cell module to a…

The essential component of expanding an undergraduate curriculum is the inclusion of lab experiments in nanoscience and nanomaterials, which significantly impact health and the environment through their use in food, cosmetics, agriculture, and medicine. We designed a laboratory experiment based on the atomic force microscopy (AFM) analysis of the…

The advantage of VLs lies in their capacity for simulating real-world lab experiences within a fully immersive digital environment, yet the uptake in rural schools in developing countries remains low. To understand this paradox, this study explores the perceptions of seven secondary school science teachers in a rural district in South Africa.…

A multistep synthesis of a novel arylidene 3­(2"H")-furanone has been designed and optimized for the second-year organic laboratory. The three-step sequence consists of a nucleophilic substitution, intramolecular cyclization, and acid-catalyzed aldol condensation, and can be carried out within two 3 h laboratory periods. The final…

A problem-solving experiment is a learning activity that uses experimental design to solve an authentic problem. It combines two evidence-based teaching strategies: problem-based learning and inquiry-based learning. The use of problem-based learning and scientific inquiry as an effective pedagogical tool in the science classroom has been well…

In an upper-division interdisciplinary laboratory experiment, students use Raman spectroscopy to highlight how the overall structure and conformational order of lipid bilayers can be influenced by their individual phospholipid composition. Students prepare a supported lipid bilayer, as a model cell membrane, by spreading liposomes made of various…