Chemistry inquiry conducted by secondary school students into material degradation in the context of sustainability

Abstract

Chemistry is essential for improving the quality of life and reducing pollution, requiring regulations, green innovations, and sustainable action. In this case, chemistry education is key not only for raising environmental awareness, but also for preparing future scientists and informed citizens capable of driving sustainable transformations through green and sustainable chemistry. An inquiry-based learning approach can link chemistry education with sustainability, allowing students to develop scientific skills, environmental awareness, and teamwork while experimenting with real-world problems. One significant environmental issue is the degradation of materials, which affects their chemical structure and functionality, requiring solutions to minimize their environmental impact. This study presents an inquiry conducted by ninth-grade secondary school students on material degradation in the context of sustainability. The inquiry is developed as a collaborative project, with students working together throughout most stages, while some tasks such as data collection and analysis were performed individually to encourage autonomy. Furthermore, the inquiry spans a full quarter, enabling students to observe long-term changes, deepen their understanding of the studied processes, and engage more deeply with the environmental issue. Among their key findings, students concluded that a period of 100 days is insufficient for the complete degradation of paper, cardboard, plastic, and metal, with the latter two showing minimal changes despite exposure to environmental conditions that favor photodegradation (solar radiation), thermal degradation (temperature fluctuations between day and night), hydrolytic degradation (humidity variations on rainy days), biodegradation (fungal growth), and chemical degradation or corrosion. Additionally, they developed explanatory models on material degradation, considering environmental factors and their impacts, which allowed them to reflect on sustainability, responsible consumption, and the importance of green chemistry. This study reveals that the students indirectly reflected on five principles of green chemistry through these findings, namely, waste prevention (principle 1), less hazardous chemical synthesis (principle 3), use of renewable feedstocks (principle 7), design for degradation (principle 10), and real-time analysis for pollution prevention (principle 11), especially during the planning and conclusion phases of the inquiry. Thus, this study concludes that inquiry-based learning is an effective approach that deepens the understanding of material degradation and its environmental impact while fostering the integration of the principles of green chemistry. This approach was well-received by students and encouraged positive emotions.