Gas-phase nitrogen oxides are important in the formation of tropospheric ozone. NO[subscript x] (NO and NO[subscript 2]) as well as tropospheric ozone have been shown to have negative effects on human health. Therefore, accurately measuring NO[subscript x] concentrations in the atmosphere is important. In this laboratory experience, students…

A clear understanding of climate change and its impacts on society is an integral component of scientific literacy today. However, college students in introductory and lower division science courses often struggle to connect with this material in a meaningful way when they do not see how it is relevant to their daily lives. To address this…

A simple and low-cost, DIY-type, Arduino-driven experiment is presented for the study of friction and measurement of the friction coefficient, using a conductive rubber cord as a force sensor. It is proposed for high-school or college/university-level students. We strongly believe that it is worthwhile planning, designing and performing Arduino…

Le Châtelier's principle is used as a basis to derive an expression to calculate solution pH during titrations that involve only strong acids and strong bases. Central to this model are the reaction quotient and a re-equilibration term that represents the extent of neutralization during a titration. Unlike the method traditionally taught to…

The separation of chamazulene from hydrophilic contaminants present in blue tansy oil provides a visually engaging example of two common techniques: extraction and thin-layer chromatography (TLC). This application uses liquid CO[subscript 2] as a lipophilic solvent to pull a brilliant blue hydrocarbon molecule, chamazulene, out of or through a…

A low-cost alternative to the typical scientific laboratory water bath or a hot plate stirrer water bath is proposed. Readily available immersion circulators have been developed for sous vide cooking. These precision cookers are designed to maintain water at an exact temperature and thus are well-suited for the similar laboratory requirements of a…

The miniaturization of flow injection analysis devices presents several improvements related to analytical procedures. However, a cost reduction and simplification are required to allow extensive use in undergraduate teaching laboratories. Here we present a low cost microfluidic electroanalytical device composed only of interlocking toy blocks,…

Expensive, highly reflective barium sulfate plates are typically used to obtain solid-state UV-vis electronic spectra. Through normal laboratory use these plates become dirty, chip, and break, thus requiring replacement. An alternative to purchasing new plates is to make your own by combining a mechanical stabilizer, such as gum arabic, with…

Fostering the development of students' critical thinking (CT) is regarded as an essential outcome of higher education. However, despite the large body of research on this topic, there has been little consensus on how educators best support the development of CT. In view of some of the controversies surrounding the teaching of CT skills in higher…

Project-based learning has been shown to be an effective pedagogical strategy that motivates students and thus promotes learning. In this article we describe a project-based unit centered on the physics of solar cookers (Fig. 1 and 3). Our goal was to elevate the solar cooker from a summer camp activity to a college-level project that could be…

Bridging organic and inorganic chemistry as well as molecular biology, this undergraduate experiment deals with the synthesis of ligands for metal complexes that can cleave DNA. Students gain theoretical and experimental expertise about metal--DNA interactions and the mechanisms behind DNA cleavage. This experiment lays a basis for the…

A teaching laboratory experiment is described where students prepare in vitro transcription reactions of a fluorescent RNA aptamer, named Broccoli, and observe the production of the aptamer in real-time on a fluorescence plate reader. Alternate visualization methods with minimal costs are also described for laboratories lacking this…

Organic semiconductors (OSCs) are making great progress as active components in alternative energy and flexible electronics technologies that are of interest to many undergraduates. However, in materials governed by the confluence of multiple length scales (molecular (Angstrom), intermolecular (nm), domain (100s nm)), providing a pedagogically…

When students first encounter energy bands in semiconductors, and how the properties of simple semiconductor devices such as the "p-n" junction diode depend on them, the concept can be a bit difficult to grasp. As part of an undergraduate physics course for non-STEM majors that includes semiconductors and simple devices based on the…

In this study 635 general chemistry I and general chemistry II students completed a 40-item Likert-scale survey on their opinions of various practices, including some academically dishonest practices, that might occur in the general chemistry laboratory. The practices surveyed were focused on areas including preparation before coming to the…