Uma proposta de perfil conceitual para reações químicas

• Autor(a) principal: DINIZ JÚNIOR, Antônio Inácio
• Data de Publicação: 2022
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRPE
• Texto Completo: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/9192
• topic: Perfil conceitual; Reação química; CIENCIAS HUMANAS::EDUCACAO

The main objective of this thesis was to propose a conceptual profile for the concept of chemical reactions. We are guided by the theory of concept profiles (MORTIMER; EL-HANI, 2014, MORTIMER et al., 2014), which allows us to understand the heterogeneity of thought and language, which implies recognizing the coexistence of two or more meanings for the same concept, often expressed by the same individual when associated with different contexts. The proposition of a conceptual profile takes into account the proposal of a genesis for the concept studied based on the development of ideas over historical time, on the experiences of individuals, and considering senses and meanings attributed to the concept through scientific and common sense languages, which are intertwined in the discursive interactions established in instructional contexts. For the operationalization of this research, we conducted a qualitative study and based on the model of proposition of conceptual profiles (MORTIMER et al., 2014), which considers the sociocultural, ontogenetic and microgenetic genetic domains for the selection of data sources representative of different ways of thinking and speaking the concept to be profiled, in this case chemical reactions. To this end, we used secondary sources from the History of Science and Philosophy of Chemistry with a focus on the concept of chemical reactions, research on students' informal conceptions of this concept and data gathered from questionnaires with high school and college students, as well as from data gathered through the application of a didactic sequence involving the plurality of the concept of chemical reactions applied to different contexts. The empirical research was carried out in two phases, the first in two high school classes of a private school in Recife, having as subjects 20 2nd grade students and 12 3rd grade students, in which we applied a remote questionnaire, containing 7 subjective questions about the theme in question. In the second phase, we applied a didactic sequence (DS) in five stages in a subject of an undergraduate Chemistry course at a public university in Recife, with the participation of 21 students. Thus, through the DS we sought to work different perspectives about the concept of chemical reactions. Regarding our results, based on the literature data analysis, at first we built a semantic matrix, considering different epistemological, ontological and axiological commitments related to the concept of chemical reactions, and then, we characterized the zones of the conceptual profile for the concept of chemical reactions, considering the different themes, categories and commitments verified in the first phase of the analysis. We propose seven zones for the conceptual profile of chemical reactions, namely: chemical transformations associated indiscriminately with any change; chemical reactions as something enlivened; chemical reactions as a natural or intrinsic process of materials; chemical reactions understood from sensations and affectivity; chemical reactions understood by evidence and changes in properties; chemical reactions understood from scientific and social applications; and chemical reactions understood as an explanatory model. In the students' answers to the questionnaire and in the analyzed data from the didactic sequence, we observed the emergence of the seven proposed zones. We emphasize that, in the didactic sequence, in which the concept of chemical reactions was worked considering the application in different contexts, the proposed profile was configured as an effective tool for the understanding of the teaching and learning process of chemistry, and can be used in the broader approach of the concept and also in relationships with other concepts or themes, such as electrochemistry environmental pollution, food, among others in the school context, considering different approaches, and beyond the school context, for example, in communities of practice, pharmaceutical laboratories, cleaning products factories, food industry, rapadura or cachaça production mills, in which the different ways of thinking and ways of talking about chemical reactions are present.