An undergraduate laboratory experiment for the synthesis of biologically significant bis-4-hydroxycoumarins using a new catalyst is described here. An experimental setup plan, monitoring the reaction by TLC, isolation of the product, safe laboratory handling procedures, and significance of data reproducibility of the result are the main learning…

A laboratory experiment was developed to introduce undergraduate chemistry students to the chemical characterization of agroindustrial waste extracts by gas chromatography-mass spectrometry (GC--MS). The students prepared hexane and dichloromethane extracts from black pepper ("Piper nigrum" L.) waste. GC--MS analysis revealed the…

Joseph Priestley, discoverer of oxygen, lived in Nantwich, Cheshire, UK, from 1758 to 1761. In 2019, an exhibition featuring his life and achievements, and also celebrating the International Year of the Periodic Table, was developed by the Nantwich Museum. The historical research of Priestley's life, development of the exhibition, and rationale…

The liquid nitrogen cloud demonstration is an effective, dramatic, large-scale demonstration to illustrate gas laws and cloud/fog (aerosol) formations for classes and large-scale outreach events. When performed at full scale, it is common to produce a cloud 20-30 feet in height. Its effect can be further enhanced by adding brightly colored…

Reaction coordinate diagrams (RCDs) are an important tool used to visualize the energetics of a chemical reaction. RCDs provide information about the kinetics of the reaction, the mechanism by which the reaction occurs, and the relative thermodynamic stability of the molecules in a reaction. Previous research studies have characterized student…

As part of ongoing research on student thinking about quantum mechanical concepts and formalism, we explored how students defined and made sense of expectation values. Previous research has focused on student difficulties when defining the expectation value for a generic operator and found that students conflate other quantum mechanical ideas with…

The role of science teachers in the formation of students' approaches to chemistry subjects is very important. Metaphors can be used as a data collection tool to determine what meanings science teachers, who are preparing to step into the teaching profession, attribute to some concepts. It is important to know how chemistry is perceived by science…

This study has two aims. The first one is to reveal the science teacher candidates' misconceptions about the density by using a four-tier diagnostic test, and the second one is to determine to what extent science teacher candidates have scientific knowledge, lack of knowledge, and misconceptions about the density. In order to achieve these aims, a…

We investigated the processes that make seductive details (i.e., interesting but irrelevant pictures and text passages in learning materials) harmful for learning scientific concepts and principles. In our experiment, students (N = 113) learned without seductive details (control condition) or with seductive details, and afterwards worked on a…

Although many laboratory experiments are available to illustrate spectrophotometric or fluorometric methods, few of them introduce the use of luminometry to students. Bioluminescence, a subtype of chemiluminescence, is produced when an enzyme-catalyzed chemical reaction gives rise to light emission. Despite the advantages of bioluminescent…

Scientific knowledge is growing rapidly, particularly in biochemistry, an interdisciplinary subject in which the courses attract diverse students with varied disciplinary interests and career goals. Thus, there is a need to teach skills and concepts in biochemistry in a way that is both compelling to a variety of learners and also relevant to…

During their first physics courses, most students struggle with mathematical concepts that are used but not fully understood, for example, the appearance of infinity in introductory physics exercises. In many cases, these concepts are critical to understanding the underlying physical phenomenon. Typically, most books do not place much emphasis on…

Kundt's tube is a popular experiment commonly used in schools, in which standing sound waves are made visible inside a glass tube. A fine powder is stirred up in areas of high sound particle velocities, so that one can measure the wavelength of the sound waves by examining the patterns created. In this way, the 'invisible' can be made visible.…

The Essential Principles and Fundamental Concepts described in Version 3 of this guide represent content that does not fall neatly within traditional science disciplines, but rather supports a focus on integrated science. Many Fundamental Concepts illustrate more than one Essential Principle. This guide presents a vision of an ocean-literate…

The traditional treatment of the electric circuit in textbooks can be criticized in at least three respects: A) Knowledge of the global aspects of the electric circuit as a system is essential for a deeper understanding. However, this is not sufficiently emphasized. B) The presentation of the term "potential difference" or…