Journal of Chemical Education最新文献

The area near the electrode surface is called the diffusion layer, and to understand electrochemistry, it is crucial that students have a knowledge of the phenomena occurring at the diffusion layer. Here, we present a demonstration and activity to visualize and analyze the expansion of a micrometer-sized diffusion layer. The electrode process involves distinct color changes of acid–base indicators in response to electrochemically generated hydroxide ion (OH^–), from water electrolysis in a homemade thin-layer electrochemical cell. A kid’s optical microscope equipped with a digital eyepiece camera was used to observe and record the formation and expansion of the diffusion layer. Analyzing the time-dependent changes in the colorful diffusion layer enables students to derive the diffusion coefficient (D) of electrochemically generated OH^–. The imaging tool presented in this activity aids in the explicit visualization and interpretation of electrode reactions and provides an excellent opportunity to discuss concentration profiles near the electrode, diffusion layer, and diffusion coefficient.

Students in a typical instrumental analysis course may learn more than 30 analytical techniques. There are more than 150 components associated with the instrumentation that they learn. To help students organize this large amount of information, we classified these components into four categories: sources, samples, discriminators, and detectors. In this work, color-coded pictograms are used to help students identify components associated with a particular instrumental technique. For example, a UV–visible spectrophotometer can be depicted by using four color-coded pictograms. Pictograms were created for instrumentation on each of the following topics: spectroscopy, electrochemistry, chromatography, elemental analysis, surface analysis, and thermal analysis. Methods to incorporate these pictograms into the instrumental analysis course and assess their effectiveness are provided.

The Journal of Chemical Education announces a call for papers for an upcoming virtual special issue on studies about the emerging applications of generative artificial intelligence (AI). Predictions abound about the expected impacts of this new technology, and as increasing numbers of chemistry educators consider ways to incorporate it in their classrooms, the need for scholarly investigations grows. The virtual special issue will collect reports on such work and seek to establish early baselines of understanding the potential presented by tools such as ChatGPT and others. The timing for the collection’s release is designed to gather information by August 2024 to help instructors contemplating use of these tools by the start of the 2024–2025 academic year in North America.

Over the course of the COVID-19 pandemic, school students suffered from a reduction in opportunities to connect with higher education institutions, meet scientific role models in person, discuss scientific career options, and carry out hands-on practical laboratory activities. Current Chemistry Investigators (CCI) is a successful electrochemistry-based STEM career intervention program, developed and evaluated through a co-creation process with teachers and students. The goals of CCI are 2-fold: first, to provide school students with career advice through tangible scientific role models and, second, to provide real-world context for the fundamentals of electrochemistry through hands-on activities. Herein, the development of a novel electro-analytical workshop from concept through to delivery with over a thousand students having taken part to date is reported. Students are tasked with solving why a battery malfunctioned through quantitative and qualitative analyses of an electrolyte using conductivity meters. Student feedback is also gathered anonymously through the use of a classroom response system (also known as “clickers”). Together with feedback from teachers, a robust evaluation is presented to measure the impact of providing tangible scientific role models and the usefulness of the workshop.

This communication shows that although some textbooks do not discuss how to apply Raoult’s law to electrolyte solutions, we should not ignore dissociation, and the van’t Hoff factor must be considered.

As e-commerce increases, the demand for packaging materials and the potential for generating waste and negative environmental impacts also rise. Packing peanuts are a type of plastic packaging material that are used to protect goods during the shipping process. Petroleum-based plastics are common packaging materials due to their low cost, light weight, and versatility. Traditional packing peanuts are made of polystyrene, which is not biodegradable and contributes to landfill waste. Starch-based packing peanuts are biobased and a more sustainable alternative. This article describes the implementation and assessment of a hands-on laboratory activity appropriate for high school students (ages 14 to 18). In the lab, students create cornstarch-based packing peanuts with different properties and carry out follow-up experiments to test the peanuts’ performance. This article includes observations and student data that were collected from implementation in four science classes predominantly at rural high schools in a Southeastern state in the U.S. This lab can be adapted to chemistry, environmental science, and physical science classes to augment lessons on topics such as polymers, polarity, bonding, and renewable and nonrenewable resources.

Microplastics have been detected in most ecosystems around the world. They affect the environment and organisms in it, including humans and possibly their health. Hence, the analysis of microplastic occurrence in the environment is highly relevant. However, there are only a few practical and easy-to-implement methods published for school use, and therefore, microplastics still receive little attention in the classroom. This review presents an approach for separation and detection of microplastic particles in sediment with secondary school students based on methods used in current research. After sieving and density separation, the fluorescence marker Nile Red is used to selectively stain microplastic particles. Subsequently, the particles can be detected using a DIY low-cost fluorescence photobox. It offers an opportunity to address the problems associated with microplastics in a school context and can be used as an example for further discussion.

This paper describes a data set of IR, MS, H-1 NMR, C-13 NMR, DEPT, and 2D NMR spectra designed for undergraduate teaching. The data files are provided as MestReNova documents containing all the available spectra for each of the 251 different compounds in the data set. The spectral data in these files can be processed, manipulated, copied, and pasted as needed by faculty to support teaching organic chemistry and instrumental analysis and for specialized courses in spectroscopy and organic synthesis. The compounds in the database were selected to provide examples for interpreting spectra and unknowns for teaching interpretation and to support teaching synthesis mechanisms. Additional MestReNova documents are provided to demonstrate how the data can be used for a variety of common undergraduate course topics─introducing IR, MS interpretation, NMR interpretation, data processing, and spectroscopy unknowns for students.

Scaffolds can be seen as a suitable tool to support students’ learning chemistry. Digital task navigators, written scaffolds that support students in solving tasks in organic chemistry, were developed, used, and evaluated for this study. A paper task navigator was further developed into a digital task navigator, which included links to explanations of special terms that were unknown to the students. The students could use the links to find these explanations if they needed them. Four newly designed digital task navigators were evaluated using questionnaires. The students rated this newly developed digital scaffold quite highly. Students who used the links to the explanations felt that these were also helpful. The results of the students’ ratings can be used to design additional digital task navigators for other topics as well as to develop this scaffold further.

Our goal as educators should be to help our students become well positioned to achieve future success. To develop effective strategies for accomplishing this objective, we must first understand the root causes of success. Thus, to best serve undergraduate students who are taking organic chemistry courses, we must understand the attributes that most significantly enable students to be successful in these courses. The current work evaluates an assessment of undergraduate students’ abilities to answer simple general chemistry questions on the first day of an organic chemistry course. The results show that this assessment, as well as some but not all of its component questions, have high ability to predict student outcomes in an organic chemistry 1 course. This type of assessment can provide a tool for instructors to easily identify high-risk students right at the beginning of the semester. The results of this study also identify some particular prerequisite knowledge and skills that are especially important for positioning students to succeed in organic chemistry courses.