The term 'experiment' is used in different ways to mean different things in school science. This study examines the meanings of 'experiment' and how they have changed in the intended chemistry curriculum (ICC) in China since the early 1950s. A mixed methodology was adopted to analyse the 11 ICC documents from a socio-historical perspective. The…

This manuscript describes a laboratory experiment that provides students with an opportunity to create conductive silver nanogrids using polymeric templates. A microcontact-printed polyvinylpyrrolidone grid directs the citrate-induced reduction of silver ions for the fabrication of silver nanogrids on glass substrates. In addition to…

Different "thought experiments" dominate teaching approaches to weightlessness, reducing students' opportunities for active physics learning, which should include observations, descriptions, explanations and predictions of real phenomena. Besides the controversy related to conceptual definitions of weight and weightlessness, we report…

Tootsie Pops, manufactured by Tootsie Roll Industries of Chicago, Illinois, are spherical hard-candy lollipops with a chocolate-flavoured, chewy center. While Tootsie Pops have been around since 1931, it was a television commercial made in 1969 that captured the attention of many. The commercial, an amusing animated cartoon, posed the following…

Medical, industrial, and basic research relies heavily on the use of viruses and vectors. Therefore, it is important that bioscience undergraduates learn the practicalities of handling viruses. Teaching practical virology in a student laboratory setup presents safety challenges, however. The aim of this article is to describe the design and…

Although nuclear half-life is vital to physics and physical science, and to sensitive societal issues from nuclear waste to the age of the Earth, a true lab on half-life is almost never done at the college or high school level. Seldom are students able to use radioactivity to actually date when an object came into being, as is done in this…

In this paper we present a novel way to demonstrate the Hall effect and study some of its main properties using basic materials and easily obtainable measuring devices.

Water has the unusual property that it expands on freezing, so that ice has a specific gravity of 0.92 compared to 1.0 for liquid water. The most familiar demonstration of this property is ice cubes floating in a glass of water. A more dramatic demonstration is the ice bomb shown in Fig. 1. Here a cast iron flask is filled with water and tightly…

A bridge rectifier is a diamond-shaped configuration of diodes that serves to convert alternating current(AC) into direct current (DC). In our world of AC outlets and DC electronics, they are ubiquitous. Of course, most bridge rectifiers are built with regular diodes, not the light-emitting variety, because LEDs have a number of disadvantages. For…

An experiment for teaching mixing intensification in reaction engineering is described. For this, a simple tubular reactor was constructed; helical static mixer elements were fabricated from stainless steel strips and inserted into the reactor. With and without the internals, the equipment operates as a static mixer reactor or a laminar flow…

A three-pot synthesis oriented for an undergraduate organic chemistry laboratory was developed to construct a fluorescent acridone molecule. This laboratory experiment utilizes Grignard addition to an aldehyde, alcohol oxidation, and iterative nucleophilic aromatic substitution steps to produce the final product. Each of the intermediates and the…

In this experiment, students carry out a halogen-metal exchange reaction of methyl 2-iodobenzoate with isopropylmagnesium chloride in THF at 0°C to afford 2-carbomethoxyphenylmagnesium chloride, which is treated with "p"-methoxybenzaldehyde to give a lactone (phthalide) product. This reaction introduces students to the modern method of…

Enzyme kinetics measurements are a standard component of undergraduate biochemistry laboratories. The combination of serine hydrolases and fluorogenic enzyme substrates provides a rapid, sensitive, and general method for measuring enzyme kinetics in an undergraduate biochemistry laboratory. In this method, the kinetic activity of multiple protein…

A semester-long research project to synthesize unique compounds designed after published metalloprotease peptide inhibitors is presented. The research project encompasses a set of nine organic chemistry reactions traditionally taught in the second semester lab course, and the procedures are derived from scientific literature. The two principle…

Over the last decade, course-based undergraduate research experiences (CUREs) have been recognized as a way to improve undergraduate science, technology, engineering, and mathematics education by engaging students in authentic discovery. CUREs have been shown to have positive benefits similar to traditional undergraduate research experiences;…