White light refracted by a glass edge or a prism might be split into the colors of the rainbow but, when restricted by a suitable arrangement of edges, might also yield a sequence of colors complementary to the rainbow. We studied the creation of these color fields experimentally with a setup consisting of RGB light-emitting diodes that cover all…

Calculating the duration of a motion when the applied net force on the moving body changes with time is usually a challenging task. In most cases, the only example of the duration of a motion when the acceleration is not constant presented to introductory physics students worldwide is the example of harmonic motion. A discussion with respect to…

In the vicinity of a critical point, the impact of a substance's chemical identity is superseded by universal critical behavior for a number of physical properties, such as visible light scattering. In this classroom demonstration, students observe a single-phase critical mixture of partially miscible isobutyric acid + water (IAW) as the…

Traditional undergraduate biochemical laboratory curricula are confronted with challenges in improving student-learning outcomes while incorporating exciting and thought-provoking research-based laboratories due to limitations with time, increased student enrollment, and high-cost laboratory resources. However, with specialized biochemical…

Over 200 years ago, Alessandro Volta published his observations of a steady voltage when a piece of electrolyte-soaked cardboard was sandwiched between two dissimilar metals. This observation initiated a century of argument as to the origin of voltaic electricity (contact vs chemical) and catalyzed practical advances, such as the first…

Nowadays, electronic devices (especially smartphones) are developed to use as an alternative tool for recording experimental data in physics experiments. This is because of the embedded sensors in a smartphone such as the accelerometer, gyroscope, magnetometer, camera, microphone, and speaker. These sensors were used in physics experiments, such…

The coefficient of restitution (COR) for a collision is usually a number between 0 and 1 depending on whether the collision is completely inelastic, or perfectly elastic or something in between. That is the usual situation for colliding spheres or a ball dropped on a horizontal surface. A different situation arises when a bat collides with a ball.…

This study focuses on the experimental demonstration of the definition of kelvin using a triple point of water (TPW) cell and estimates the measurement uncertainty. The first part of this article is to construct the measurement setup and perform the measurements. The second stage is related with the calculation of uncertainty according to guides…

In the present study, atmospheric pressure, an abstract concept that learners generally have difficulty understanding and explaining, was presented to pre-service elementary teachers (PSTs) with the method of argumentation. The argument levels of the PSTs were examined using the Predict-Observe-Explain (POE) experiments in teaching the subject of…

Quantum dots are colloidal semiconductor nanocrystals that display size-dependent electronic and optical properties. These materials are a visual demonstration of a quantum-mechanical effect. Here we present a laboratory exercise for undergraduate/Bachelor students as an introduction to colloidal nanocrystals and quantum dots. The students…

In this paper, we present a concise and technique-heavy route to the synthesis of dimedone for a second-year organic chemistry curriculum. Our preparation of dimedone guides students through a Michael addition followed by a Dieckmann cyclization, basic ester hydrolysis, and thermal decarboxylation, while allowing time for mechanistic discussion…

The synthesis of a [2]rotaxane through three- or five-component coupling reactions has been adapted to an organic chemistry experiment for upper-division students. The experimental procedure addresses the search for the most favorable reaction conditions for the synthesis of the interlocked compound, which is obtained in a yield of up to 71%.…

Metabolic Control Analysis (MCA) is a systems biology approach that measures the control of a metabolic step on the overall flux of a metabolic pathway. In undergraduate courses in biochemistry, learning of MCA can be encouraged by experimental activities demonstrating practical applications of the MCA theory. In this work, we present a laboratory…

An understanding of basic organic chemical reactivity is key for many biosciences students. The reactivities of different carbonyl groups affect their function in many biomolecules. A practical class, the two-step synthesis of paracetamol, has been devised to illustrate the electrophilic reactivities of carbonyls, which was covered in the…

Calorimetry is a central concept in the first semester general chemistry curriculum, and constant pressure (coffee-cup) calorimetry is a common experiment in the laboratory. However, constant volume (bomb) calorimetry is traditionally reserved for the physical chemistry laboratory. This article describes the advantages of incorporating bomb…