Comparative study on the difficulties in solving stoichiometric problems in chemistry classes between a private and a public institution

Abstract

Understanding stoichiometry requires a high level of conceptual mastery and mathematical skills, and it is an area that often presents greater learning problems. Therefore, this study sought to identify the difficulties in solving stoichiometric problems among students studying chemistry, addressing the differences in mathematical skills in two educational institutions (private and public). The quantitative, non-experimental research began with a diagnostic test, structured at basic, elementary, and advanced levels of complexity, to identify errors in problem solving. The test was validated by experts and had a Cronbach's α of 0.826. It was administered to 43 students from the public institution and 47 from the private institution. In both groups, deficiencies were identified in the conceptual area to identify limiting and excess reactants, purity, yield, nomenclature, and procedural balancing of equations, construction of compounds, oxidation numbers, conversion between units such as grams, moles, and particles; numerical interpretations, molar relationships, confusion in basic calculations, which affected subsequent calculations. However, Student's t-test determined that students from the private institution performed better in solving stoichiometric problems than those from the public institution (7.25 vs. 8.06; p < 0.01). Finally, to overcome these gaps, it is important to promote pedagogical strategies that aim to improve mathematical skills and enhance students' conceptual and procedural areas of chemistry