Electromagnetic radiation can be classified into two major types depending on its ability to detach electrons from atoms: ionising and non-ionising. The aforementioned categorization is significant due to the effects of ionising radiation on human tissue (e.g. carcinogenesis). However, many students around the globe cannot distinguish these two…

Abundant prior research has compared effects of physical and virtual manipulatives on students' conceptual learning. However, most prior research has been based on conceptual salience theory; that is, it has explained mode effects by the manipulative's capability to draw students' attention to conceptually relevant (visual or haptic) features.…

Torsional effects influence kinetic selectivity in a wide range of organic transformations. As such, textbooks commonly use Newman projections to illustrate the torsional effects that arise in their transition states. Unfortunately, these representations fall short when the reaction occurs "within a ring." In many cases, the torsional…

One of the goals of science education is to help students make sense of the world around them. To that end, it is critical that students understand the central ideas in each discipline like, in chemistry, energy and interactions. These ideas are of particular importance because they are directly related to one another and are relevant across other…

An application for visualizing the dynamic properties of an equimolar binary mixture of isotropic reactive particles is presented. By introducing a user selectable choice for the activation energy, the application is useful to demonstrate qualitatively that the reaction rate depends on the above choice and on temperature. The application is based…

The VSEPR model has well-established limitations in its ability to represent accurate molecular and electronic geometries of simple molecules, which can create a significant need for students to relearn structure and bonding concepts in organic chemistry. We present an alternate method for describing molecular geometries and electronic structures…

A new undergraduate inorganic chemistry laboratory experiment is presented. An introduction of the spectrochemical series and ligand exchange is explored using the coordination complex dirhodium tetraacetate, Rh[subscript 2](OAc)[subscript 4]. Students have measured the absorption spectra of the Rh[subscript 2] complex in the presence of various…

Models that are used to predict and explain phenomena related to molecular vibration and rotation are ubiquitous in physical chemistry, and are of importance in many related fields. Yet, little work has been done to characterize student use and application of these models. We describe the results of a multi-year, multi-institutional qualitative…

The growing popularity of flipped, blended, and online learning, combined with the need to support a student population with increasingly diverse backgrounds, has led to the development and use of online materials to support students' learning of chemistry outside of a face-to-face classroom. Chemistry simulations provide opportunities to make…

Getting students to understand the particulate nature of matter is a major challenge for chemistry education. In upper secondary school students commonly struggle to distinguish between intra- and intermolecular bonding and analyse chemical bonding in terms of electronegativity. In this study, we explore how creative drama may be used in chemistry…

Students collect magnetic susceptibility data to verify that Hund's rule correctly predicts electronic configurations. Systems examined include three commercially available lanthanide(III)-containing complexes of the form M(acac)[subscript 3](H[subscript 2]O)[subscript 2] (where M = La(III), Nd(III), and Gd(III), and acac denotes the [CH[subscript…

For six semesters, activities have been incorporated into first year general chemistry courses in an effort to build student conceptual chemistry knowledge. The activities follow a learning cycle pedagogy (similar to Process Oriented Guided Inquiry Learning or POGIL activities) and consist of guiding questions involving animations, models,…

This work seeks to elucidate undergraduate science students' basic knowledge of concepts related to the energy changes for a simple heating curve and their ability to integrate related concepts. The participants were drawn from first and second semester General Chemistry classes, as well as junior/senior level Physical Chemistry classes at a…

Activation energies form an energy barrier to a chemical reaction taking place. Simple collision theory, i.e. that particles need to collide to react, would suggest that activation energy is the energy needed to overcome a coulombic barrier provided by the negatively charged electrons contained within energy shells surrounding an atomic nucleus.…

In 1827, Robert Brown noticed pollen suspended in water bouncing around erratically. It wasn't until 1905 that Albert Einstein provided an acceptable explanation of the phenomenon (Kac 1947): Brownian motion is the random movement of particles (e.g., pollen) in a fluid (liquid or gas) as a result of collisions with atoms and molecules. Movement of…