Uma análise de livros didáticos sobre o modelo atômico de Dalton em relação à argumentação e ao uso da história da ciência

Abstract

The teaching of atomic models in high school natural sciences textbooks appears to be fragmented, as a discourse whose parts are poorly connected: (a) from the linguistic point of view, as a set of statements that are not completed in coherent reasoning and whole; and (b) from the historical point of view, by not explicitly relating each atomic model with the facts that contributed to its elaboration. The present work aims to analyze how Dalton's atomic model has been approached in natural science textbooks for high school, approved by the National Textbook Program (PNLD) 2021, in relation to historical and argumentative aspects. We analyzed seven natural science textbooks. To do so, we elaborated a historical narrative about Dalton's atomic model and based it on Toulmin's Argumentative Pattern. We analyzed seven textbooks qualitatively. The analysis of the historical content was based on a list of items considered important in the didactic use of historical content, drawn from the literature. The analysis of the arguments was based on the constituent elements of Toulmin's Argumentative Pattern. The results of the historical analysis show that, in general, the description of Dalton's scientific ideas is lacking; the history of science is presented as a simple chronology, based on dates and names; the specific motivations and problems that led Dalton to elaborate his atomic theory are not adequately explored; there are historical content errors. The results of the argumentative analysis reveal that most textbooks do not present satisfactory argumentation from the point of view of Toulmin's Argumentative Pattern and the content of Dalton's Atomic Model, with some specific exceptions. This indicates that books can contribute little to the understanding of Dalton's atomic model and to the development of students' argumentative capacity on the subject. Therefore, more research is needed on the contributions of the history of science and/or argumentation in the teaching of Dalton's atomic model in Basic Education. There is a need for the elaboration of argumentative didactic texts on Dalton's atomic model, in order to favor the construction of knowledge, as well as the contribution to the development of students' argumentation. We conclude that the fragmentation identified in the preliminary review extends to the analyzed textbooks. Therefore, these books can contribute little to help students build Dalton's atomic model, despite the PNLD requiring that textbooks use the history of science and argumentation. Faced with the historical and argumentative shortage found in textbooks, it is essential to carry out more investigations on the use of the history of science and argumentation in chemistry teaching. Furthermore, it is necessary to elaborate historical-argumentative didactic texts on Dalton's atomic model.