In chemical synthesis, obtaining product(s) with high purity is a crucial issue from both academic and industrial viewpoints. Higher purity of the product(s) means higher quality and a lower chemical production costs. Sometimes, purification and separation processes are very laborious and lead to significant impacts on the final price of the…

The study aimed to investigate the effect of computer simulation and animation-integrated instruction on preservice science teacher trainees' conceptual understanding and retention of acid-base chemistry and stoichiometry. A quantitative approach with a pretest-posttest-delayed test quasi-experimental design was used. In the study area, there were…

The pharmacologically active lignans sesamin and sesamolin are minor components of sesame oil and ingredients in OTC dietary supplement capsules. We report an introductory undergraduate organic laboratory experiment combining natural product isolation and spectral analysis in which students isolate a mixture of sesamin and sesamolin by either (1)…

The basic knowledge of chemical formula writing is fundamental for chemistry students, yet many still struggle to learn it. To provide a more interactive and engaging approach that facilitates and reinforces student understanding of chemical formulas and stoichiometry of chemical reactions, we have designed a chemical jigsaw puzzle. Only eight…

Theoretical yield and extent of reaction (degree of completion) are important concepts in stoichiometry and in chemical kinetics. We provide expressions describing theoretical yield (Y) and maximum extent of reaction (fractional yield, f[subscript max]) for five examples of commonly encountered reversible chemical reactions: A [equilibrium sign]…

This is an easy and inexpensive laboratory experiment in which undergraduate students at the Bachelor's degree level in Chemistry can measure formation constants of complexes [Ni(en)[subscript n](OH[subscript 2])[subscript 6-2n]][superscript 2]+ (n = 1, 2 or 3; en = ethylenediamine) through an acid-base titration. The background information…

The paper presents the design and evaluation of a voluntary online introductory stoichiometry (VOIS) course aimed at facilitating the transition from secondary to higher education. The course utilized simple analogies and adaptive feedback through a formative scaffolding assessment. The study assessed the effectiveness of the VOIS course through…

The goals of the study were as follows: i) to design an active science learning activity on stoichiometry for grade 10 students, ii) to evaluate the academic achievement of grade 10 students after receiving an active science learning activity on stoichiometry, and iii) to investigate the perspectives of grade 10 students regarding an active…

This activity allows students to visualize how to obtain different stoichiometries with various techniques in a single experiment. The involvement of three phases adds to the student's interest. Instructional materials are provided to facilitate the experimental procedures, interpretation of results, and error analysis. The reaction of Li from a…

The aim of this qualitative case study was to explore secondary students' ability to transfer among representation levels in relation to stoichiometry. In the study, 40 students in the 11th grade from two classes of an Anatolian high school in the east part of Turkey were selected as sample group. The data were collected by using a questionnaire…

The purpose of this study was to examine how learners' problem-solving approaches and success changed from high school to graduate school. This case study included 15 participants who were purposefully selected regarding their grade levels. To examine the development, we asked three algorithmic questions and three problems, which were different…

Over the past decade the Accreditation Board for Engineering and Technology, Inc. (ABET) has changed the general chemistry requirements to include a single introductory course for most engineering majors. There is a focus on outcomes that equip students with the ability to pass the Fundamentals of Engineering (FE) Exam and to work in…

High school students find reaction stoichiometry and the concept of the mole hard to comprehend. Teachers are well aware of the importance of teaching the mole concept and also the difficulty associated with it. In an attempt to improve the understanding of the mole concept with reduced difficulty, an atomic model kit that provides a hands-on…

Stoichiometry calculation competence tends to be particularly poor in the developing world, even among teachers. Various methods, including the unit factor method, have the potential to be effective in developing such competence. To evaluate the likelihood of such a generic proportion method, which downplays traditional formula usage, succeeding…

This article presents and discusses the results of an educational innovation that seeks to introduce the world of molecular gastronomy in chemistry lessons as a means to review stoichiometry and offer an alternative way to learn. In the literature to date, there is no evidence of haute cuisine having been employed to contextualize stoichiometry…