Chemistry Education Research and Practice最新文献

The current study aims to contribute to the literature on how organic chemistry students weigh various factors when predicting products of substitution and elimination reactions. This study focuses specifically on these mechanism types, as they are often the first instances where students must consider the “how” and the “why” of how reactions occur. Previous literature highlights that such reasoning can be challenging. To better support our students, it is essential to understand how they conceptualize these mechanisms. Here, we present results from an investigation into how students compare bimolecular and unimolecular substitution and elimination reactions (S_N1, S_N2, E1, E2). Students completed tasks involving case comparisons and “predict-the-product” exercises. Through the analysis of nine semi-structured interviews using coordination class theory, we found that (1) students placed a greater emphasis on the importance of the starting substrate in the outcome of a reaction, and (2) focused less on the function of the nucleophile or base in each reaction. Using coordination class theory, we identified visual features and knowledge elements that students coordinated, allowing us to create “resource graphs” that represented students’ conceptualizations. These graphs helped visualize the trajectories of students’ predictions by illustrating how they balanced multiple factors. We discuss implications for supporting students in distinguishing among reaction mechanisms.

During their first year of study at university, many students encounter challenges in developing learning strategies that align with success in the courses in which they are enrolled. The emergence of the COVID-19 pandemic heightened the challenges as universities were compelled to transition to online learning. Therefore, this study investigated the self-reported use of learning strategies in a first-year chemistry course delivered online due to the COVID-19 pandemic to identify learning strategies associated with success. Grounded in self-regulated learning (SRL) theory, a case study approach with an explanatory mixed methods design was adopted. Quantitative data were collected using a hybrid of the Motivated Strategies for Learning Questionnaire and the Online Self-regulated Learning Questionnaire. Follow-up open-ended questions were emailed to the students for the qualitative part of the study. Statistical analysis of the quantitative data was performed using SPSS and RUMM2030, while thematic analysis was applied to the qualitative data. Students reported more frequent use of SRL strategies of environment structuring, effort regulation, and elaboration. Conversely, critical thinking, task strategies, help-seeking, and peer learning were reportedly used less often. SRL strategies linked with success in the course were identified as effort regulation, goal setting, and time management. The findings from the qualitative data revealed an impact of online learning due to the pandemic on the use of peer learning and help-seeking strategies. The paper discusses the implications of these findings for educational practices, particularly in the context of hybrid learning in the post-pandemic era.

General chemistry is often the first course taken by students interested in careers in STEM and health fields, and therefore, is considered an essential course for the success and retention of students in these fields. Prior studies have shown study habits and skills to be related to student performance in college-level courses, including STEM courses. Previous chemistry studies have focused on deep versus surface approaches to studying, how affective variables (e.g., self-efficacy) affect study habits, and how students study week to week. Literature has also shown that students’ management of their general study time can impact their performance, with distraction while studying becoming an increasing challenge for students. This study examined first-semester general-chemistry students' study behaviors (both their explicit learning strategies and study-time management practices) focusing on their exam preparation and that relationship to exam performance when controlling for prior knowledge and class attendance. Key findings include: (1) students, on average, employed two active strategies for exam preparation, dedicated half of their study time to active strategies, and were distracted 26% of the time. (2) While active strategies positively influenced exam performance and passive strategies had a negative impact, not all active strategies were equally effective. (3) The percentage of study time spent on active strategies correlated positively with performance, whereas higher distraction levels during exam preparation negatively affected outcomes. Understanding student exam-study behaviors and their effects on exam performance can help instructors support students more effectively by teaching them study strategies effective for their courses.

Effective learning in chemistry education requires students to understand visual representations across multiple conceptual levels. Essential to this process are visuospatial skills which enable students to interpret and manipulate these representations effectively. These abilities allow students to construct mental models that support problem solving and decision making, improving their understanding of complex concepts, for example chemical structures and reactions. The impact of individual differences in mental imagery, such as aphantasia and hyperphantasia, on chemistry students’ spatial thinking when engaging with visual representations is not well understood. This paper presents two exploratory studies that examine how the vividness of mental imagery is related to student outcomes in chemistry-related visuospatial problem solving. The first study quantitatively assessed the performance of first-year university students in tasks requiring complex visual and spatial reasoning within a chemistry context. The second study, involving the same participants, used qualitative interview data to investigate their cognitive strategies with a focus on how their mental imagery impacts their problem-solving approaches. Preliminary results suggest that the vividness of students’ visual mental imagery did not significantly impact their ability to spatially reason with visual representations in chemistry. Our findings also indicate that students with aphantasia may employ alternative strategies that mitigate their lack of visual mental imagery. This paper highlights the need for further research into the diversity of cognitive mechanisms employed by chemistry students of varying mental imagery capabilities.

This study investigates if a force-based teaching approach, based on quantum mechanical principles and developed in a lesson study, would enhance the understanding of chemical bonding among upper secondary school students. The teaching approach was based on research on the teaching and learning of chemical bonding. The study included first-year students in upper secondary school in a pretest–intervention–posttest design. During four lessons the students were introduced to the underlying forces leading to the formation of all chemical bonds, specifically focusing on ionic- and covalent bonds. The first lesson, which included a presentation of coulombic interaction as a common basis of bond formation, was developed and improved through a lesson study. The lesson was revised based on feedback from 75 students describing why chemical bondings occur. After the four-lesson series about chemical bonding, a total of 67 of the 75 enrolled students had completed both a pre- and a posttest. The students’ answers to the tests were analyzed based on Bernstein's theory of vertical hierarchical and vertical horizontal discourse. The results of the posttests show that 60% of the students demonstrated solely or predominantly vertical hierarchical knowledge structure. These results indicate that most of the students could understand the force-based approach of chemical bonding by using a general theory, spanning over a wide range of the natural science field, with an abstract and specialized language. Moreover, the students who internalized a hierarchichal knowledge discourse about chemical bonding earned higher final grades in the upper secondary school chemistry when compared to students using a horizontal knowledge discourse, indicating that a force-based approach might facilitate a deeper understanding of other subareas within chemistry. In chemistry education research, the effect of using a force-based approach to teach chemical bonding has not previously been widely tested among upper secondary school students. This study responds to the need to test alternative teaching models to facilitate students’ understanding of chemical bonding.

This paper describes the design and evaluation of the rganic chemistry epresentational ompetence ssessment (ORCA). Grounded in Kozma and Russell's representational competence framework, the ORCA measures the learner's ability to interpret, translate, and use six commonly used representations of molecular structure (condensed structures, Lewis structures, skeletal structures, wedge-dash diagrams, Newman projections, and chair conformations). Semi-structured interviews with 38 first-semester organic chemistry learners informed the development of the ORCA items. The ORCA was developed and refined through three pilot administrations involving a total of 3477 first-semester organic chemistry students from multiple institutions. The final version of the ORCA was completed by 1494 students across five institutions. Various analyses provided evidence for the validity and reliability of the data generated by the assessment. Both one-factor and three-factor correlated structures were explored via confirmatory factor analysis. The one-factor model better captured the underlying structure of the data, which suggests that representational competence is better evaluated as a unified construct rather than as distinct, separate skills. The ORCA data reveal that the representational competence skills are interconnected and should consistently be reinforced throughout the organic chemistry course.

Many undergraduate chemistry students hold alternate conceptions related to resonance—an important and fundamental topic of organic chemistry. To help address these alternate conceptions, an organic chemistry instructor could administer the resonance concept inventory (RCI), which is a multiple-choice assessment that was designed to identify resonance-related alternate conceptions held by organic chemistry students. In this study, two iterations of the RCI were administered to undergraduate organic chemistry students: the RCI-Pilot (N = 484) and the RCI-Final (N = 595). Evidence was collected to support the quality of the RCI items, the validity of the data obtained with the RCI based on internal structure, and the reliability of the data obtained with the RCI. Classical test theory (CTT) was utilized to determine the quality of the items. To gather validity evidence, the Rasch model was used and a differential item functioning (DIF) analysis was conducted. Reliability estimates were made using McDonald's Omega. Since validity and reliability evidence was gathered for the assessment scores, the data obtained in this study supports the use of the 14-item RCI for detecting student alternate conceptions with resonance.

This study reviewed the green and sustainable chemistry education (GSCE) research that provided training at the tertiary level from 2000 to 2024. The Web of Science and ERIC databases were screened using title and abstract review. In total, 49 studies were analysed. The analysis instrument has two main parts, namely, general characteristics of the training, which was formed in light of the GSCE literature (i.e., chemistry sub-disciplines, type of implementation, and context), and analysis of the training through the lens of pedagogical content knowledge (PCK) construct that is the commonly-used framework for the analysis of training regarding orientation to teaching GSCE, learner, curriculum, assessment, and instructional strategies utilised. Results showed that organic chemistry (n = 15) is the most emphasised branch of chemistry in the articles. Regarding the learner component, the studies were inadequate, and very few studies provided information about the misconceptions and difficulties that students may encounter while learning GSC. Regarding the curriculum component, among the green chemistry principles, ‘use of renewable feedstocks’ was the most emphasised, while the least emphasised ones were ‘reduce derivatives’ and ‘real-time pollution prevention’. Fourteen studies used subject-specific teaching strategies (e.g., cooperative teaching and project-based strategies). Although representations are not used in GSCE, most of the studies included laboratory studies (n = 31). Finally, regarding the assessment, very few studies focused on measuring students' skills (laboratory skills, discussion skills, etc.) and affective variables. In light of the findings, GSCE training should get more benefit from the literature on science/chemistry teaching strategies. Moreover, alternative assessment tools (e.g., rubrics and concept maps) should be utilized regarding the instruments utilized to assess the participants' GSC knowledge.

The current study ascertained the influence an instructional module had on enhancing students’ understanding of chemical reactions and acid–base topics. The sample size for this study consisted of 197 students, including 101 in an “experimental” group and 96 in a “control” group, selected from schools in two Districts (Rwamagana and Musanze) in Rwanda, Africa. The experimental and control groups received a pre-test and post-test to collect data. In addition, focus group discussions (FGDs) were conducted with students in the experimental group. Further, a test question analysis was used to evaluate the students’ content knowledge of chemical reactions and acids, bases, and pH. To analyze the research data, the Statistical Package for the Social Sciences (SPSS) software was used for quantitative analysis. The independent t-test results indicated no significant difference between the means of the control and experimental groups at the pre-test stage (df = 195, p = 0.380). At the post-test stage, a statistically significant increase was observed in the mean scores of the experimental group compared to the control group (df = 195, p < 0.001), showing that the intervention effectively improved student learning outcomes in chemistry education.

Immersive Virtual Reality (iVR) can help students visualise and explore complex chemical concepts, such as protein enzyme structures and interactions. We designed a set of collaborative iVR-based learning tasks on the interaction between a protein enzyme and its substrate. We investigated how 18 pairs (36 students) in undergraduate chemistry courses changed their understanding of enzyme–substrate interactions through iVR learning tasks. Videos of pre- and post-interviews and student-generated diagrams were analysed. Before iVR, students had abstract models of the structure of a protein enzyme or its interaction with a substrate molecule. Over 90 per cent of the students (33/36) explained enzyme–substrate interactions using simplistic lock-and-key diagrams, exclusively focusing on the shape. Although many students employed key scientific terms like activation energy in their explanations, they were unsure how enzymes lowered activation energy or how catalytic reactions occurred. After iVR, all students discussed the inadequacy of 2D diagrams for representing complex enzyme–substrate interactions. About 90 per cent of students (32/36) used concrete ideas such as electron density and orientation of reactants in the active site to explain the probability of successful interactions between the enzyme and its substrate. Our findings provide evidence of how interactive iVR learning tasks can help students explore complex molecular structures, integrate ideas, and build a concrete understanding of challenging science concepts.