This interdisciplinary study sketches the ways in which proportional reasoning is involved in the solution of chemistry problems, more specifically, problems involving quantities in chemical reactions (commonly referred to as stoichiometry problems). By building on the expertise of both mathematics and chemistry education research, the present…

Identifies the misunderstandings and problem-solving strategies of secondary students when solving stoichiometry problems. (Author/CCM)

Analyzes students' attempts to answer examination questions involving stoichiometry and chemical equilibrium and reports that the majority of the students do not fully understand either concept. Concludes that the main difficulty with these topics is that they are highly abstract and first taught to students before they have reached the stage of…

Investigates reasoning strategies students use in solving stoichiometric problems and explores the relation between these strategies and alternative conceptions, prior knowledge, and cognitive variables. Results show how stoichiometric relations produce conflicting situations for students leading to conceptual misunderstanding of certain concepts.…

The purpose of this descriptive study was to create and test questions on stoichiometry with number ratios for quick mental calculations and to identify students' problem-solving strategies. The present study was a component of a more comprehensive investigation in which 7,441 German senior high school students were asked to work on 154 test items…