Green chemistry is the name of a need, that of encompassing chemistry research and the environmental, safety, health, and societal issues that have been creating unprecedented concerns at a global level. Green chemistry is a modern concept, as the label that represents the entry of chemical sciences in the realm of integrated sustainability…

This paper mainly proposes a simple method to record scattered light rays via photography, presenting a clearer and brighter representation of the optical path. This technique is applied to the double-slit interference experiment and single-slit diffraction experiment typically conducted in general physics courses, and shows the intuitive results…

Practical hands-on experience is an effective component of science education. Lessons that involve demonstrations allow learners to explore and verify information learned from other sources (for example, reading a textbook). As a demonstration for use in a science educational setting, we developed a way to make a variable focal length lens using a…

Carefully scaffolded dynamic visualizations have potential to promote science learning for all students, including English language learners (ELLs) who are often underserved in mainstream science classrooms, but little is known about how to design effective scaffolding to support such diverse students' learning with dynamic visualizations. This…

For 26 years, it has been assumed by some that the thermodynamics of open-system biochemical reactions must be executed by performing Legendre transformations on the terms involving the species whose concentrations are being held fixed. In contrast, standard nontransformed thermodynamics applies to chemical processes. However, it has recently been…

In this study, we visualized the superposition principle of sound waves in a both-closed-end (BCE) resonance tube. The resonance tube is constructed using an acrylic tube with 2.64 cm internal diameter and 150 cm length, polystyrene beads to illustrate the positions of displacement nodes and antinodes and two identical detachable speakers as…

Within the new world perspective, it is expected that the school, as a formal education space, will be able to provide students with the basic information regarding human knowledge accumulated over the years, and also help them be capable of understanding various scientific and technological issues present today. In the specific case of knowledge…

The ubiquitous bouncy ball, or "superball," is an engaging child's toy that has endured for more than 50 years. But what makes a bouncy ball so uniquely suited to its name? Steel balls, for example, are more highly elastic than are butadiene bouncy balls. Yet it is butadiene balls, and not steel balls, that appear in toy stores and…

In this article we consider a well-known simple, very accessible demonstration of surface tension with a small boat propelled by substances that change the surface tension of water. A simple quantitative evaluation is provided that matches well with experimental data. A modification to the experiment is proposed allowing it to continue for a long…

Quantitative demonstration of chemical kinetics often requires sophisticated equipment and materials. By using inexpensive and commonly available chemicals, we propose here two clock reactions, oxygen-safranin-benzoin clock and cysteine-iodine-hydrogen peroxide clock. Students simply measure and add stock solutions to start clock reactions. Sudden…

Ray diagrams are widely used in introductory physics textbooks to illustrate the behavior of ideal systems of lenses or mirrors in geometrical optics. Their virtue lies in their explicit display of multiple ray paths connecting object and image points, which leads naturally to an understanding of how a planar object is transformed into a planar…

High voltage supplies are often used in physics classes for demonstrations and laboratory work. These devices deliver several thousand volts DC, while limiting the current to a safe level, typically under 5 mA. One issue with these power supplies is their expense, which means schools may not have one. Less expensive homemade units have been…

It is well known that when two waves are added they produce beats. These beats are the amplitude modulation of the initial waves and occur periodically at a rate equal to the frequency difference of the two waves. Acoustical beats arise from sound waves of nearly equal frequencies. Optical beats arise from the interference of two light waves of…

The various radiation types that make up the electromagnetic (EM) spectrum are ubiquitous and highly significant in modern society. Detection of visible light by the eye facilitates sight, radio waves and microwaves are used in communication technologies, x-rays are used in medical imaging, and gamma rays are frequently employed in medical…

Work, kinetic energy (KE), and potential energy (PE) are key physics concepts, taught in essentially every introductory physics course along with the physical laws such as the work-kinetic energy theorem and the conservation of mechanical energy, which describe how the values of those quantities change during various processes. Quite appropriately…