Chemistry Education Research and Practice最新文献

A recent study in Chemistry Education Research and Practice highlights the common pattern of student thinking known as ‘the octet framework’, and notes how it seems to relate to, but be inconsistent with, the octet rule: an idea commonly taught in introductory chemistry classes. The study noted the common feature of learners extending the octet rule into ‘a driving force’ for chemical change, but analysis also noted two other features of the alternative conceptual framework. It is argued here that these research findings reflect a key problem in chemistry education: one that the research community should prioritise for further investigation.

We explored chemical engineering students’ approaches to learning, study-related burnout, and perceptions of peer and self-assessment in a challenging physical chemistry thermodynamics course. Cluster analysis revealed three learning profiles based on students’ approaches to learning: students who scored high in both organised studying and the deep approach to learning, students who scored high in the unreflective approach to learning, and students who scored high in all three approaches. According to our findings, students who employed deep learning strategies and managed their time carefully experience the least study-related burnout. These students also felt more efficacious when participating in assessment and had fever negative experiences of both peer and self-assessment. Consequently, physical chemistry educators should adopt practices that facilitate a deeper approach to learning, including paying careful attention to course workload and utilising teaching methodologies that can foster the deep approach like peer and self-assessment.

This study aims to determine the cognitive structures of students at different educational levels (8th grade and 12th grade) related to acid–base chemistry. The research was designed as a case study and structured in two stages. The first stage analyzed concepts related to acid–base chemistry and their direction and strength in students’ knowledge structures. The second stage determined the descriptive and structural features of students’ knowledge structures related to acid–base chemistry in a more holistic approach. The study was carried out with a total of 160 students, 80 grade 8th and 80 12th grade students. A word association test (WAT) and the free writing technique (FWT) were used together. In the WAT, ten different frequency ranges were determined forming cognitive structure maps of the students. With high-frequency values on the map, it was found that the number of stimulus and response words decreased but the strength of associations increased. In frequency ranges where the frequency values of associations were low, it was found that the number of stimulus and response words increased and the cognitive structure organization was at the most advanced level compared to other frequency ranges, but the strength of associations was weak. In general, it was observed that there were no bidirectional and cross-associations between the concepts in the cognitive structures of the students about chemistry and that there was a static structure that included one-way associations only. Additionally, the concepts in the cognitive structures of students related to acid–base chemistry were analyzed in terms of their structural characteristics. It was found that, in the cognitive structures of the students there were no associations between many concepts that should be related to each other.

When teaching STEM courses, it is important to introduce state-of-the-art techniques. Students need to learn how to conduct experiments, analyse data and choose the most effective approaches to address meaningful situations. Here we present the assessment of the implementation of a structured inquiry-based activity aimed at teaching students about protein mass and size. This activity emerges as an intervention in our educational module, designed to create a cognitive conflict that effectively drives a conceptual change. To evaluate the efficacy of this module, we collected data on students’ perceived and actual knowledge through pre- and post-class surveys (n = 36 and 34, respectively, mean age 26 ± 2). Additionally, we evaluated lab reports using a detailed rubric. Results indicate that the practical innovation we propose is a challenging activity that promotes the accomplishment of our learning objectives. The activity led to improvements both in confidence and in actual mastery of theoretical concepts and techniques. After completing the activity, students were able to choose the most appropriate technique to solve specific problems. Furthermore, we found that the use of a structured questionnaire in lab reports helped students to accurately analyse and process experimental data. It also allows them to demonstrate understanding of technical limitations, while integrating the knowledge and skills acquired during the module. Overall, this activity provides notions that are conceivable and profitable, thus leading to successful conceptual changes.

Laboratory work in chemistry has been extensively researched in the last decade but the gap between research and practice is still broad. This Perspective shares 10 guiding principles relating to university laboratory education, drawing on research over the last decade. Written with an audience of practitioners in mind, the Perspective aligns with Hounsell and Hounsell's congruence framework, so that the 10 principles consider all aspects of the laboratory curriculum: design, teaching approaches, and assessment approaches as suggested by Biggs, but additional contextual factors relating to teaching context: backgrounds of students and their support, and overall laboratory organisation and management. After discussing the rationale for each guiding principle, examples of approaches are given from recent literature along with prompts to help enact the guiding principle in practice.

Appealing to students' affect in academic settings, such as demonstrating chemistry's relevance to their life, is one strategy instructors may use to support students’ in learning. This study investigates the types of connections that students make to organic chemistry when responding to an open-ended writing assignment. Students enrolled in an introductory level organic chemistry course were asked to choose and write about an organic molecule they felt was important to their life, in doing so students wrote about the molecule's relevance to their life. Analysis of the writing was supported by semi-structured interviews with a subset of the students in which they discussed their approach to completing the assigment. Conclusions from this study suggest that students successfully made connections between their chosen moleucle and their life. Considered through the lens of relevance, students can both seek and find relevance in organic chemistry topics on a personal, societal, or vocational level; and therefore may reinforce their comprehension and appreciation of chemistry.

Education in organic chemistry is highly reliant on molecular representations. Students abstract information from representations to make sense of submicroscopic interactions. This study investigates relationships between differing representations: bond-line structures, ball-and-stick, or electrostatic potential maps (EPMs), and predicting partial charges, nucleophiles, and electrophiles. The study makes use of students’ answers in hot-spot question format, where they select partially charged atoms on the image of a molecule and explanations. Analysis showed no significant difference among students when predicting a partially positive atom with each representation; however, more students with EPMs were able to correctly predict the partially negative atom. No difference was observed across representations in students predicting electrophilic character; while representations did influence students identifying nucleophilic character. The affordance of EPMs was that they cued more students to cite relative electronegativity indicating that such students were able to recognize the cause for electron rich/poor areas. This recognition is central to rationalizing mechanisms in organic chemistry. This study offers implications on incorporating EPMs during instruction and provides evidence-based support in how EPMs could be useful in promoting learning on topics that relate to an uneven charge distribution.

Asking students to explain why phenomena occur at a molecular level is vital to increasing their understanding of chemistry concepts. One way to elicit students’ mechanistic reasoning and guide construction of knowledge is through Writing-to-Learn (WTL), which is a promising approach for students in organic chemistry courses. In the design of WTL assignments, rhetorical aspects provide an authentic context by designating a role, genre, and audience for students. This context can support students’ learning, but, if the rhetorical aspects misalign with the learning objectives of the assignment, they can hinder students’ ability to achieve these objectives. In this project, we designed a WTL assignment about a base-free Wittig reaction, which we implemented in an organic chemistry laboratory course. Here, we explore how changes in the rhetorical aspects of this assignment can influence the way students explain two different comparisons of reaction mechanisms. We consider how students use explicit and implicit properties and how the use of these features compares within the context of the reaction. Results indicate that, when the rhetorical aspects align with the learning objectives of the assignment, students provide more productive elaborations that use both explicit and implicit properties. This is supported by both the analysis of students’ writing and students’ feedback about the assignments.

Education researchers are deeply interested in understanding the way students organize their knowledge. Card sort tasks, which require students to group concepts, are one mechanism to infer a student's organizational strategy. However, the limited resolution of card sort tasks means they necessarily miss some of the nuance in a student's strategy. In this work, we propose new machine learning strategies that leverage a potentially richer source of student thinking: free-form written language justifications associated with student sorts. Using data from a university chemistry card sort task, we use vectorized representations of language and unsupervised learning techniques to generate qualitatively interpretable clusters, which can provide unique insight in how students organize their knowledge. We compared these to machine learning analysis of the students’ sorts themselves. Machine learning-generated clusters revealed different organizational strategies than those built into the task; for example, sorts by difficulty or even discipline. There were also many more categories generated by machine learning for what we would identify as more novice-like sorts and justifications than originally built into the task, suggesting students’ organizational strategies converge when they become more expert-like. Finally, we learned that categories generated by machine learning for students’ justifications did not always match the categories for their sorts, and these cases highlight the need for future research on students’ organizational strategies, both manually and aided by machine learning. In sum, the use of machine learning to analyze results from a card sort task has helped us gain a more nuanced understanding of students’ expertise, and demonstrates a promising tool to add to existing analytic methods for card sorts.

Numerous studies have proven the learning benefits of concept maps in science subjects, particularly for students with low prior knowledge. There is a scarcity of research dedicated to the examination of chemistry courses at the university level, and the findings pertaining to academic performance in that subject exhibit a lack of consistency. This study examined the impact of concept maps on students of a General Chemistry course who had low prior knowledge. The study applied a quasi-experimental design to collect data on two topics: uncertainties of measurements (Topic 1) and acid–base (Topic 2). Fill-in-the-nodes concept maps were developed and served as learning materials. ANCOVA and Johnson–Neyman techniques were used to analyze the scores of concept tests of Topic 1 and Topic 2, respectively. In both Topics 1 and 2, the results showed that the treatment group outperformed the control group. However, the aforementioned finding was limited to the subset of students whose pre-test scores were below 30.7 out of a total of 47. From the analysis of the attitude questionnaire, the authors concluded that the students appreciated the usefulness of concept maps. However, they might hesitate to engage in using this new learning tool. The study's findings strengthen the evidence of the learning benefits of concept mapping. Moreover, using concept maps in teaching is feasible because of their low cost and minimally invasive modification to instructional design. The practices for implication of concept mapping are also discussed.