With an awareness of the considerable discomfort of graduate students in grasping the crux of key concepts of voltammetry and its variants, I present an inexpensive and user-friendly hands-on setup based on the fabrication of a rotating platinum electrode to facilitate teaching the tenets and applications of hydrodynamic voltammetry (HV). Readily…

A laboratory project to introduce upper-level undergraduates to Pd-catalyzed C-N [sigma]-bond forming reactions is described. The exercise involves evaluation of monodentate phosphine ligands and solvents for the Buchwald-Hartwig coupling of 4-chloro-or 4-bromo-anisole with morpholine. Students gain experience in the synthesis of a biarylphosphine…

This paper reports a demonstration of a 90 min on-demand class where a chemical experiment is performed to educate nonscience majors on surfactants. First-year undergraduate students perform the water ball in a water bottle experiment at home and learn about the structure and properties of organic compounds in the demonstration. The experiment is…

The study aims to learn that they want to reflect on their reflective thoughts and reveal how they reflect what they have learned. Reflective thinking, one of the higher-order thinking skills, enables students to learn more easily and permanently. Students with high reflective thinking skills will be more successful both in their academic and…

This research aimed to explore the conceptual structure of chemical equilibrium in upper-secondary school students using factor analysis. Research on chemistry education has shown that chemical equilibrium is an important but difficult-to-understand topic. Exploring the conceptual structure of chemical equilibrium among students will help…

Iodonium zwitterions are hypervalent iodine compounds in which the iodine center binds to two substituents and carries a positive formal charge which is compensated by a negative charge within the same molecule. Under thermodynamic conditions, iodonium zwitterion sallow concerted nucleophilic aromatic substitutions to be performed, followed by…

The biological world includes many negatively valenced activities, like predation, parasitism, and disease. Do children's books cover these activities? And how do parents discuss them with their children? In a content analysis of children's nature books (Study 1), we found that negatively valenced concepts were rarely depicted across genres and…

In the transition from classical to modern physics, the idea of taking some certain quantities as distinct or bounded values and keeping the rest continuous has proved useful in dealing with many problems. In this paper we assume an upper bound on the velocity of classical particles and indicate that applying this assumption to electromagnetism…

The motion of a cylindrically or spherically symmetric body on an accelerated treadmill, inclined of an angle [theta] with respect to the horizontal, is described by means of Newtonian mechanics. By assuming that the conveyor belt has an acceleration "a[subscript O][superscript ']", not necessarily constant, and that the body rolls on…

The Earth's shape concept develops as consecutive cognitive problems (e.g., the location of people and trees on the spherical Earth) are gradually resolved. Establishing the order of problem solving may be important for the organisation of teaching situations. This study attempted to determine the sequence of problems to be resolved based on tasks…

Didactic transposition theory examines the development from scientific/academic knowledge being produced by scientists to it becoming learned knowledge constructed by learners. According to the theory, four kinds of knowledge exist: scientific knowledge, knowledge to be taught, taught knowledge and learned knowledge. In this study, learning and…

Studies have shown that inadequate definitions of scientific concepts could complicate the learning of science and could prevent students from understanding the definitions of scientific concepts. The article provides a framework for defining scientific concepts in primary, secondary, and university education by proposing teachers draw attention…

Interactive simulations allow students to independently explore scientific phenomena and ideally infer the underlying principles through their exploration. Effectively using such environments is challenging for many students and therefore, adaptive guidance has the potential to improve student learning. Providing effective support is, however,…

This manuscript is meant to support secondary school teachers in their constant effort to find novel ways to engage students. Adolescents seem particularly stimulated by time-travelling scenarios, like the famous "wormhole billiard ball paradox" proposed by J. Polchinski in 1990, which are usually solved through closed time-like curves…

Chemistry is one of the important branches of science. The subject matter of chemistry consists of numerous complex and abstract concepts. Therefore, sometimes students have flawed understanding of these concepts. These erroneous concepts are known as misconceptions. The purpose of this study was to investigate the misconceptions for Valency and…