Emphasizing stoichiometry appears to be a norm of introductory chemistry courses. In this longitudinal and mixed-methods study, we examined how the emphasis on stoichiometry in assessments of introductory chemistry impacted educational equity and student learning. Using quantitative methods, we identified mole and stoichiometric conversions as two…

Learners underperform in stoichiometry as they lack conceptual reasoning of the underlying concepts and the ability to solve stoichiometric problems. Therefore, it was necessary to determine if there is a statistical correlation between problem-solving skills and conceptual reasoning in stoichiometry and if so, whether one can significantly…

The study sought to find out difficulties encountered by high school chemistry students when solving stoichiometric problems and how these could be overcome by using a problem-solving approach. The study adopted a quasi-experimental design. 485 participants drawn from 8 highs schools in a local education district in Zimbabwe participated in the…

A series of pedagogical problem set exercises are posed that illustrate the principles behind material efficiency green metrics and their application in developing a deeper understanding of reaction and synthesis plan analysis and strategies to optimize them. Rigorous, yet simple, mathematical proofs are given for some of the fundamental concepts,…

A coding scheme is presented and used to evaluate solutions of seventeen students working on twenty five stoichiometry problems in a think-aloud protocol. The stoichiometry problems are evaluated as a series of sub-problems (e.g., empirical formulas, mass percent, or balancing chemical equations), and the coding scheme was used to categorize each…

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…

This activity introduces students to the concept of reduction-oxidation (redox) reactions. To help students obtain a thorough understanding of redox reactions, the concept is explored at three levels: macroscopic, submicroscopic, and symbolic. In this activity, students perform hands-on investigations of the three levels as they work at different…

A model of expertise in chemistry problem solving was tested on undergraduate science majors enrolled in a chemistry course. The model was based on Anderson's "Adaptive Control of Thought-Rational" (ACT-R) theory. The model shows how conceptualization, self-efficacy, and strategy interact and contribute to the successful solution of quantitative,…

A qualitative case study was conducted to investigate the understanding of the limiting reagent concept and the strategies used by five Year 11 students when solving four reaction stoichiometry problems. Students' written problem-solving strategies were studied using the think-aloud protocol during problem-solving, and retrospective verbalisations…

The international literature suggests students frequently resort to the use of formulae when solving stoichiometry problems without understanding the concepts. In prior work we identified Thai student alternative conceptions and ability to solve numerical problem for stoichiometry. The results indicate that many Thai students also hold alternative…

Stoichiometry and related concepts are an important part of student learning in chemistry. In this interpretive-based inquiry, we investigated Thai Grade 10 and 11 students' conceptual understanding and ability to solve numerical problems for stoichiometry-related concepts. Ninety-seven participants completed a purpose-designed survey instrument…

This study examines Indonesian students' understanding of conservation of matter, balancing of equations and stoichiometry. Eight hundred and sixty-seven Grade 12 students from 22 schools across four different cities in two developed provinces in Indonesia participated in the study. Nineteen teachers also participated in order to validate the…

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.…