Photochemical reactions are the reactions that are induced by light. Many of these reactions are found in natural processes, including photosynthesis and the formation and decomposition of ozone in the atmosphere. Classroom demonstrations are effective in enhancing students' learning and retention. Herein, we have developed a simple demonstration…

In this paper, a simple method is described for visually demonstrating that the wavelength of light reduces when entering a medium of higher refractive index. When a violet laser (405 nm) is reflected off the surface of a Blu-ray disc (track spacing 320 nm) diffraction cannot occur since the wavelength is greater than the track spacing. However,…

Plant leaves are green because they contain the green photosynthetic pigments, chlorophylls a and b. Popular science literature, and sometimes even textbooks, state that the greenness is caused by reflection of green light by chlorophyll. In the present study, we compared the reflectance spectra of green leaves to yellow or white leaves of the…

The Arduino microcontroller is currently one of the favorite tools of makers, and many teachers have used it in teaching or experiments. In addition, light-emitting diode (LED) smart lighting is the worldwide trend in lighting. There are many teaching demonstrations or applications of color addition using LEDs. Furthermore, the Internet of Things…

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…

Using polymerizable cholesteric liquid crystal (CLC) paints, we prepare circularly polarized freestanding films that enable students to acquire a basic understanding of circular polarization and molecular chirality. The polymerized helical structures of CLC films can exhibit brilliant structural colors by selective reflection of visible light…

In this study, we describe a method to employ a conventional compound light microscope, usually available in laboratories, to obtain fluorescence. In particular, two pieces of colored acrylic plastic were utilized to assist the microscope in filter performance. We also attempted to examine the applicability of the setup by staining onion cells…

Light spectrum dispersion is an exciting subject in science because of its beautiful atmospheric colour phenomenon which attracts students. However, to see the phenomenon is not easy since it needs a spectrometer, which is commonly expensive. Therefore, the present study aims to describe a low-cost spectrometer for investigating lighting spectrum…

The current pandemic era demands distance learning, including physics experiments on the topic of optics. One of the optical phenomena that needs to be explained in optic courses is fluorescence. This study offers a simple home experiment regarding the application of fluorescence, namely to identify the purity of olive oil using simple…

Pulse oximetry has become the standard of care in operating rooms, intensive care units, and hospitals worldwide. A pulse oximeter continuously and noninvasively monitors the functional oxygen saturation of hemoglobin in arterial blood (Sa[subscript O2]). Sa[subscript O2] is so important in medical care that it is often regarded as a fifth vital…

Many of us teach that insects can see "invisible" ultraviolet light, but what demonstrations do we perform to illustrate this? Often UV can be used to cause fluorescence or phosphorescence, which can make its existence more visible. But, is it possible to create photographs or videos that convincingly illustrate the vision of insects? In…

Diffraction is an important phenomenon in physics. This paper describes using a scanning electron microscope (SEM) to produce cross-sectional images of iridescent seashells. When seashell cross-sections are viewed in a SEM, regular structure is seen. Seashells are a good example of a biocomposite material and good natural objects for introducing…

Nanochemistry is an important aspect of modern chemical science. Though few educational institutions teach nanochemistry as a formal course, general exposure of students to nanoscience is yet important. Thus, we present a nanochemical activity that could be used as part of many chemistry courses or laboratories based on ChemToy2. This activity is…

There has been dramatic growth in interest and research regarding organic photochromism in recent decades. Despite this, the topic is seldom addressed in the undergraduate chemistry curriculum. Herein, we present a straightforward and robust experiment for the second semester organic chemistry laboratory curriculum which combines multistep…

This work presents an experiment that seeks to simulate human color vision through electronic components in an attempt to build, together with the students, a cybernetic 'eye'. The limitation of the cybernetic eye developed here in relation to the standard human chromatic vision, which makes it a 'colorblind eye', is an argument to be explored by…