Carla Morais

Abstract An acid-base titrator connected to the Internet was developed for conducting remote investigative experiments. The experiment was broadcasted in a high school senior classroom, with the presence of a facilitating teacher. The activity required students to determine the indicator present in the solution. To carry out the activity, students added acid or base to sweep the pH range from 0 to 14 and noted the corresponding coloration to the pH through video analysis. The results obtained were very satisfactory, both in the identification of the indicator and in the acceptance and engagement of the students in the activity.

Abstract Given the challenges associated with understanding electrochemistry content by engaging in prediction, observation, and explanation, laboratory activities can foster active participation and critical thinking, enabling individuals to proactively confront and revise their understanding. Since pre-service teachers should gain firsthand experience with predict-observe-based on a predict-observe-explain strategy, we propose a laboratory activity presented as a mystery box related to concentration cells coupled with an Arduino-based electronic data measurement system to identify how pre-service chemistry teachers move from observations to inferences in a qualitative research. Data was collected by written records and oral explanations during the practical interactions. Results suggest that the proposed laboratory activity allows pre-service chemistry teachers to access data and correct inferences related to electrochemistry content, promoting critical thinking. Data also showed a connection between the macroscopic and symbolic domains, and pre-service teachers recognized concepts associated with the activity, such as solution conductivity and the potential difference in chemical reactions, interpreting the system with prior knowledge, like electron flow direction and concentration cell components. However, additional strategies are needed for detailed and consistent observation and inference recording, enhancing the potential of such activities in favoring electrochemistry education in high schools.

Abstract This paper investigates a proposal for teaching Green Chemistry concepts through the implementation of a Problem-Based Learning (PBL) approach in a specific and optional course on the subject in higher education. The main objective was to analyze the effect of implementing Problem-Based Learning (PBL) didactics on understanding Green Chemistry principles within a course with 8 university students. Through this methodology, students analyzed case studies involving the identification of GC principles in industrial redesign processes and the problematization of controversial situations related to the importance of discussions on chemical processes. Two specific cases, bio-based butylene glycol and enzymatic treatment of paper, were used to test students' ability to recognize and justify the relevance of these principles. Additionally, another activity about the synthesis of acetanilide allowed students to identify which of four methodologies could be considered the greenest, considering different aspects. The research revealed that although the PBL approach effectively engaged students and deepened their understanding of GC principles, some concepts presented challenges. Certain principles of Green Chemistry, such as atom economy and catalysis, proved complex for some students, leading to confusion and challenges in assessing the greenness of processes. Nonetheless, students demonstrated improved knowledge and practical application of GC principles, linking them to industrial processes like bio-based material production and analyzing the benefits and drawbacks of different methods for producing the same substance. This study highlighted the value of a dedicated PBL approach with adequate resources to foster discussions and understanding. However, elective courses often attract only those already familiar with the subject, limiting broader engagement and field expansion. Disparities in case material quality, particularly for bio-based butylene glycol and acetanilide production, underscored the need for well-structured resources. Future research should include larger sample sizes for statistical validation and more class time for discussions and supplemental activities. This study contributes to the literature on active learning strategies, showcasing PBL's potential to enhance sustainable chemical education.

Abstract <jats:p>Student-centred learning requires a variety of approaches, such as inquiry-based learning and the tackling of authentic and problem-based learning activities, to make the teaching and learning process more meaningful and to encourage students to participate more actively in class. The inquiry approach enables students to investigate solutions to real problems, awakening their need to ask questions, design and conduct research, collect and analyse data, interpret results and present them in a structured way. This study investigates the influence of an inquiry-based science education (IBSE) module on the development of oral and written communication skills among 10th grade students. The study is set in a secondary school context and focuses on a problem-based learning approach centred around gases and dispersions. A total of 111 students participated in this one-group post-assessment qualitative study, where evaluation rubrics were applied to assess students’ written and oral communication, focusing on correctness, clarity and mastery of scientific language. The results showed that the majority of students performed well in both written and oral tasks, demonstrating improved scientific communication skills. This suggests that IBSE, particularly in the context of secondary education, can be an effective approach to fostering students’ abilities to communicate scientific concepts. The study has implications for enhancing pedagogical practices and encourages further research on the long-term effects of IBSE on student learning.</jats:p>