Although transition-metal-catalyzed reactions are important in contemporary organic chemistry, relatively few resources for the second-year organic chemistry curriculum discuss the subject. The inquiry-based experiment described here, an iron-catalyzed preparation of biphenyl from bromobenzene, introduces this topic. The reaction uses an…

Water transport in tall trees is an everyday phenomenon, seldom noticed and not completely understood even by scientists. As a topic of current research in plant physiology it has several advantages for presentation within school physics lectures: it is interdisciplinary and clearly shows the connection between physics and biology; the…

An experiment to verify the Doppler effect of sound waves is described. An ultrasonic source is mounted at the end of a simple pendulum. As the pendulum swings, the rapid change of frequency can be recorded by a stationary receiver using a simple frequency-to-voltage converter. The experimental results are in close agreement with the Doppler…

A selection of hands-on experiments from different fields of physics, which happen too fast for the eye or video cameras to properly observe and analyse the phenomena, is presented. They are recorded and analysed using modern high speed cameras. Two types of cameras were used: the first were rather inexpensive consumer products such as Casio…

Using first principles, a theoretical equation for the maximum and actual muzzle velocities for a pneumatic cannon was recently derived. For a fixed barrel length, this equation suggests that the muzzle velocity can be enhanced by maximizing the product of the initial pressure and the volume of the propellant gas and decreasing the projectile…

Physics students are usually unaware of the limitations and functions of related principles, and they tend to adopt "hot formulas" inappropriately. This paper introduces four real-life examples for bridging five principles, from fluids to thermodynamics, including (1) buoyant force, (2) thermal expansion, (3) the ideal-gas law, (4) the 1st law,…

This paper continues the collection of experiments that describe the use of cell phones as experimental tools in physics classroom education. We describe a computer-aided determination of the free-fall acceleration "g" using the acoustical Doppler effect. The Doppler shift is a function of the speed of the source. Since a free-falling objects…

As part of an NSF-funded Course Curriculum and Laboratory Improvement (CCLI) project that seeks, in part, to increase student exposure to scientific instrumentation, a gas chromatography experiment has been integrated into the second-semester general chemistry laboratory curriculum. The experiment uses affordable, commercially available equipment…

This paper deals with the study of a toy CD hovercraft used in the fluid mechanics course for undergraduate students to illustrate the lubrication theory described by the Stokes equation. An experimental characterization of the toy hovercraft (measurements of the air flow value, of the pressure in the balloon and of the thickness of the air film…

Adding mint Mentos candy to a two-liter bottle of Diet Coke produces a fountain of soda foam that can reach 3 m high. A demonstration such as this can get a "Wow" out of most audiences, usually followed by a "Do it again!"--but can it be used to teach anything? The answer is a definite "Yes," and what follows is a guided inquiry activity that…

Used since the time of the ancient Egyptians as a method for transferring liquids from one vessel to another, the siphon is a dependable tool. Although, the act of siphoning beer from a fermentation barrel or wine from a demijohn is a skill that has been passed down from generation to generation, do we really know how the siphon works? It is…

Coulometric titrations involve the quantification of analyte by measurements of current and time. In most coulometric titrations, the anode and cathode are placed in isolated cells that are connected by a salt bridge. By contrast, the experiments described here involve coulometric titrations (of acidic protons in solution) using a silver anode and…

In this extension to a classic physical chemistry experiment, students record the proton nuclear magnetic resonance spectra of the [beta]-diketones 2,4-pentanedione, 3-methyl-2,4-pentanedione, and 3-chloro-2,4-pentanedione to investigate the effect of substituents on keto-enol tautomerization equilibria. From the integrated intensities of keto and…

Molecular biologists commonly use bioinformatics to map and analyze DNA and protein sequences and to align different DNA and protein sequences for comparison. Additionally, biologists can create and view 3D models of protein structures to further understand intramolecular interactions. The primary goal of this 10-week laboratory was to introduce…

In 1984, a teacher was successfully prosecuted by the Health and Safety Executive. The case centred around chemically prepared hydrogen that was dried by bubbling it through concentrated sulfuric(VI) acid and then passed over hot copper(II) oxide. The procedure was often carried out quantitatively to find the mass of copper in a sample of…