Approximate mathematical treatments are commonly taught in undergraduate chemistry, but the validity ranges of these approximations have rarely been properly defined. We present error contour plots of commonly used quadratic approximations for calculating equilibrium proton concentrations of monoprotic acids. Students and instructors can easily…

Laboratory activities are a prevalent and essential part of chemistry learning because of their potential to help students develop problem solving abilities, visualize chemistry concepts learned in lecture, and gain practical skills. However, learning in the laboratory environment is not without its challenges. For example, cookbook-style…

Incorporating an evidence-based approach in STEM education using data collection and analysis strategies when learning about science concepts enhances primary students' discipline knowledge and cognitive development. This paper reports on learning activities that use the nature of viscosity and the power of informal statistical inference to build…

Chemistry curriculum should account for learning in context and understanding chemistry at the macroscopic and microscopic levels: the symbol level and the process level. The "Taste of Chemistry" learning module, developed for high school chemistry majors (students who choose to study the advanced chemistry program in high school),…

Spontaneity criteria for processes with useful (especially electrical) work have been discussed based on total differentials of thermodynamic functions. Reaction Gibbs energy ([Delta][subscript r]G) and electrochemical reaction Gibbs energy ([Delta][subscript r]G~) have been juxtaposed. Three-dimensional graphs showing the dependencies of…

One challenge associated with introducing systems thinking in chemistry classrooms is the increase in content complexity that students face when they engage in this type of approach. Placing core chemical ideas within larger systems has promise, as long as students are not overwhelmed by the added complexity. Although there are many potential…

Explanations of phenomena in chemistry are grounded in discussions of particulate-level behavior, but there are limitations to focusing on single particles, or as an extension, viewing a group of particles as displaying uniform behavior. More sophisticated models of physical processes evoke considerations related to the dynamic nature of bulk…

This research considered students' abilities to read images about dispersed systems, taken from the chemistry textbook. 103 high school students (37 males, 63 females, and 3 unknown) from the school "Svetozar Markovic" in Novi Sad, Republic of Serbia, were included as the research participants. Students' abilities to suggest the titles…

Chemical equilibrium is one of the most important concepts in chemistry. The changes in properties of the chemical system at equilibrium induced by variations in pressure, volume, temperature, and concentration are always included in classroom teaching and discussions. This work introduces a novel, geometrical approach to understanding the…

Change over time is a crosscutting theme in the sciences that is pivotal to reaction kinetics, an anchoring concept in undergraduate chemistry, and students' struggles with rates of change are well-documented. Informed by the education scholarship in chemistry, physics, and mathematics, a research team with members from complementary disciplinary…

The oxidation of iron is an important reaction due to its high economic impact. In this laboratory exploration, the total order of this reaction was determined using commercially available handwarmer packets that rely on the iron-oxygen reaction to generate heat. The active ingredient in the handwarmer packet is iron, which interacts with…

Box-and-whisker plots or simply boxplots are powerful graphical representations that give an overview of a data set. In this work five different examples illustrate the applications of boxplots in food chemistry. The examples involve relative sweetness of sugars and sugar alcohols with respect to sucrose, the potassium content of fruits and…

The elementary reaction sequence A ? I ? Products is the simplest mechanism for which the steady-state and quasi-equilibrium kinetic approximations can be applied. The exact integrated solutions for this chemical system allow inferring the conditions that must fulfill the rate constants for the different approximations to hold. A graphical…

This study uses graphs of conductivity measured by a microcomputer-based laboratory (MBL) to promote students' macro, micro, and symbolic representations when learning about net ionic reactions (NIR). A total of 54 students, aged 14-15 years old participated in this research, and were randomly divided into an experimental group (N = 27) and a…

Many students enroll in college general chemistry with an interest in a medical career. In those (and alternative) careers, they will need to make critical decisions about data and how that data are acquired. A significant portion of introductory lab experiments are, in principle, but not necessarily in practice, devoted to understanding how…