Combustíveis automotivos: um olhar estequiométrico e comparativo sobre a emissão de um gás do efeito estufa pela queima da gasolina e do etanol

Abstract

Stoichiometry in Chemical Reactions is one of the contentes, of High and Higher Education, more difficult to be understood by the student. This work sought improvements to the teaching of Stoichiometry, through a contextualized class, and used the theme of automotive fuels, gasoline and ethanol, to work with their combustion reactions. The contextualization broadened the objective of this project, providing that the worsening of the greenhouse effect as a result of the emission of carbon dioxide in the terrestrial atmosphere, by burning these fuels, was addressed. This research was carried out in an academic environment, with a class of the Curricular Component of General Chemistry, which encompassed several courses in the area of Engineering. It took place through four distinct didatic moments, each with its own purpose: previous questionnaire, presentation of a vídeo, contextualized class and final questionnaire. The data were evaluated, so that categories and theories emerged during the investigative process. It was observed that the Stoichiometry presentes itself as a difficult contente, exposing some deficiencies of the students, in relation to topics associated with it, such as balancing, Chemical connections; however, it was found that contextualization, as a learning methodology, can be a useful resource, as it was well accepted by all students.