This article argues that the role of practical work in science is overemphasised and misunderstood. Science is distinguished by the fact that it is a set of ideas about the material world and not by empirical enquiry. The latter is only one of six styles of reasoning that have been used to develop scientific ideas. The lack of clarity around the…

One of the most mystifying products on the market for people at any age is the glow stick: a plastic tube that, when snapped, creates a flood of bright, brilliantly colored light without the use of electricity or significant production of heat. In this case, the chemiluminescence reaction also provides an exciting phenomenon through which we can…

The blue bottle experiment is a popular chemical demonstration because of its simplicity and visual appeal. Most papers on the topic focus on a new formulation or a new presentation, but only a few discuss pedagogical application for a full lab session. This article describes the use of this experiment in the first session of undergraduate…

The electrophilic addition of a hydrohalic acid (HX) to an alkene is often one of the first reactions learned in second-year undergraduate organic chemistry classes. During the ensuing discussion of the mechanism, it is shown that this reaction follows Markovnikov's rule, which states that the hydrogen atom will attach to the carbon with fewer…

Carbon nanomaterials have promising utility in chemical sensing including applications in preserving occupational safety, monitoring of environmental pollution, and human health. While recent advances in device fabrication and molecular design of functional materials have enabled rapid fabrication of chemical sensors from carbon nanomaterials,…

In this study, we present an activity in which the free-body diagram of a real stationary object on an inclined plane can be examined interactively. We use an Apple Watch and a few other materials that can be accessed easily. Instead of an Apple Watch, a mobile phone or a tablet could also be used. This activity may be employed to introduce the…

The different ways microscale and green chemistry allow reducing the deleterious impacts of chemistry on human health and the environment are discussed in terms of their different basic paradigms: green chemistry follows the ecologic paradigm and microscale the risk paradigm. A study of the synthesis of 1-bromobutane at macro- ? microscale (109.3…

Characterization of the vapor pressure of a volatile liquid or azeotropic mixture, and its fluid phase diagram, can be achieved with an isoteniscope and an industrial grade digital pressure sensor using the experimental method reported in this study. We describe vapor-pressure measurements of acetone and n-hexane and their azeotrope, and how the…

This paper presents a successful, free inquiry experiment in which students devise an experiment to measure carbon dioxide in an important chemical, biological, or environmental situation. Also discussed is rationale for adopting an open inquiry experiment and how it fits into the laboratory as a whole. Typical student projects are given, and data…

The synthesis of 1,1-diphenylethylene (DPE) via a Grignard reaction, followed by an acid-catalyzed dehydration reaction, yields a mixture of compounds. DPE is a high boiling liquid that cannot be purified using simple distillation. However, it is easily separated from the more polar starting material and intermediate alcohol using both thin layer…

In this experiment for an upper-division course in organic structure determination, each student prepares an unknown compound and characterizes the product using multiple spectroscopic techniques. The unknowns, 2-aryl-substituted 1,4-dihydro-3,1-benzoxazines and 1,2,3,4-tetrahydroquinazolines, are prepared in a single step by the condensation of…

The noise level from exploding chemical demonstrations and the effect they could have on audiences, especially young children, needs attention. Auditory risk from H[subscript 2]- O2 balloon explosions have been studied, but no studies have been done on H[subscript 2]-air "eggsplosions." The peak sound pressure level (SPL) was measured…

The dramatic decrease in the cost of sequencing a human genome is leading to an era in which a wide range of students will benefit from having an understanding of human genetic variation. Since over 90% of sequence variation between humans is in the form of single nucleotide polymorphisms (SNPs), a laboratory exercise has been devised in order to…

Here, we describe the implementation a hybrid general chemistry teaching laboratory curriculum that replaces a portion of a course's traditional "wet lab" experiences with online virtual lab modules. These modules intentionally utilize representations on all three levels of the chemistry triplet-macroscopic, submicroscopic, and symbolic.…

The purpose of this research was to design and develop hands-on practical physics activity for the determination of relationship between the fundamental frequency and wavelength of standing waves using open or closed resonance tubes. In this study, an innovative use of smartphone device for the hands-on practical activity was developed with the…