Química verde em foco: uma proposta pedagógica no ensino de Química orgânica experimental II

Abstract

The current context involving severe environmental problems brings to light one of humanity’s greatest challenges: rethinking our way of life and the relationship we establish with nature. Considering the role of education and science, particularly Chemistry, this study focused on how to problematize environmental issues, with an emphasis on applying the principles of Green Chemistry, defined as "the use of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products." The main objective of the study was to investigate how the application of Green Chemistry principles in the teaching of Organic Chemistry, through practical experiments, can promote meaningful learning. Specifically, the synthesis of acetylsalicylic acid (ASA) was explored as an example of optimizing chemical reactions to make them more sustainable and safer. The research was defined as qualitative-quantitative and employed a project-based pedagogical approach. The reactions were analyzed in terms of mass efficiency, atomic economy, and E-factor, aiming to reduce the use of toxic reagents and material waste. At the end, students responded to a questionnaire to evaluate the methodological proposal. The experiments demonstrated that reducing the amount of reagents and replacing the catalyst with a less toxic option resulted in lower waste generation and a more sustainable synthesis. The results also showed that, even with significant changes in parameters, the quality of the products was not compromised. Additionally, the questionnaires revealed that most students were unfamiliar with Green Chemistry before the activity, but the approach was considered challenging and meaningful, encouraging the adoption of these principles in their future activities in Chemistry teaching. Finally, by providing practical and reflective learning, future teachers developed a more critical perspective on the importance of Chemistry in everyday life, preparing themselves to act as agents in forming conscious citizens.