Resumen de How Are Students Solving Familiar and Unfamiliar Organic Chemistry Mechanism Questions in a New Curriculum?
Declan M. Webber, Alison B. Flynn
In this study, we continue our efforts to address students’ difficulties understanding organic chemistry, particularly in connecting structure to function and using the language of chemistry to explain how and why reactions occur. For the first time, we have characterized students’ work and problem-solving strategies on familiar and unfamiliar mechanism questions in a new course format: a patterns of mechanisms organic chemistry curriculum and flipped course format. This study began with analysis of students’ exam answers then more deeply explored the features to which they attend and their strategies using a think-aloud interview protocol. Success rates were higher on both the familiar and unfamiliar mechanism questions in the new course format with medium effect sizes, although we cannot conclude a causal link with the new format. Interview analysis revealed that all used the electron-pushing formalism correctly and as an initial and routine part of their problem-solving strategy. Most participants regularly used concepts of nucleophiles, electrophiles, electronegativity, and charges (full and partial) in their problem-solving process. Participants used dipoles and charges (full and partial) to reveal nucleophilic and electrophilic portions of molecules, often expanding structures to do so. In difficult questions or steps, successful strategies involved expanding and mapping in combination with chemistry reasoning. Every participant struggled with an acronym in one question, LDA, wanting to draw its structure and identify its role but not being sure they could remember it. That difficulty drawing the structure became a barrier to analyzing the reactivity. To emphasize the importance of connecting structure and reactivity over memorizing, we recommend drawing out structures and not only acronyms on assessments. In this article, we describe the context, methods, findings, and implications for research and instruction.
