masterThesis
Dificuldades de aprendizagem em estequiometria: uma proposta de ensino apoiada na modelagem
Fecha
2013-07-30Registro en:
SANTOS, Livia Cristina dos. Dificuldades de aprendizagem em estequiometria: uma
proposta de ensino apoiada na modelagem. 2013. 154 f. Dissertação (Mestrado em Ensino de Ciências Naturais e Matemática) - Universidade Federal do Rio Grande do Norte, Natal, 2013.
Autor
Santos, Livia Cristina dos
Resumen
In order to learn/teach chemistry some themes are relevant, like the stoichiometry,
which consists in the study of the weight ratios in the combination of elements and
compounds between themselves. This is an underlying subject in the
understanding/representation/forethought of chemical reactions. Considering these
aspects, our study presents a modeling-based proposal to develop the content of
stoichiometry with prospective chemistry teachers. With this aim, we have made a
review of literature, which we considered when tried to identify the learning difficulties
using both quizzes and pedagogical tests, and then, from those difficulties we could
propose a teaching unit for this concept and, consequently the evaluation of our
proposal. The participants were chemistry undergraduates at the Universidade Federal
do Rio Grande do Norte (UFRN) from assorted levels. As a methodological
framework, we rely on the discursive textual analysis to characterize the speech of
participants. As main results we observed ideas of appearance or disappearance of
matter during chemical transformations, disregard of stoichiometric proportions when
using drawings to represent the microscopic level of a reaction and confusion between
the magnitude amount of matter and other magnitudes such as mass and volume. The
final product is a sequence of instruction, based on the modeling previous research
literature , with the goal of improving students ability to articulate the macroscopic and
submicroscopic levels of representation of the matter