Evidence of Student Learning of Spectrophotometry and Intermolecular Forces in the Chemistry Laboratory

This dissertation investigates how undergraduate students engage with analytical methods and foundational concepts in the general chemistry laboratory with attention to meaningful learning and mechanistic reasoning. Using these frameworks three laboratory activities explored student perceptions and explanatory reasoning in the context of laboratory learning. The first strand of the research analyzed student perceptions of spectroscopy in contrast to gravimetric analysis through the methodological framework of phenomenography and then used the phenomenographic outcome space to redesign the curricular instruction and assessment. Analysis of student reports revealed four qualitatively distinct conceptions of spectrophotometry, with meaningful learning evident where students connected spectrophotometric measurements to light-matter interactions, expressed engagement with lab process, and articulated confidence in their findings. In a novel use of the phenomenographic outcome space, the laboratory activities were restructured through revised sequencing, added preparatory conceptual work, and procedural simplification guided by the categories of description from the phenomenographic study. Additionally, assessment was explicitly aligned with the outcome space. Comparative analysis of pre- and post-intervention showed marked improvement in students’ conceptual accuracy, procedural fluency, and attitude toward spectrophotometry. The second strand analyzed student reasoning and resource activation in a laboratory activity on intermolecular forces (IMFs) where they were asked to explain the appearance of water droplets on glass slides that were modified with alkoxysilanes. The lab engages students in constructing explanations that bridge macroscopic observations and submicroscopic representations, promoting causal reasoning grounded in molecular structure and surface chemistry. This laboratory development was followed by an analyzes of students’ written explanations of their observations using a causal mechanistic reasoning (CMR) framework. Findings indicate that while students often articulated appropriate CMR in homogeneous systems, their reasoning for heterogeneous systems generally lacked submicroscopic coherence. To support this, a CMR analysis map was developed to visualize conceptual resources, levels of representation, and explanatory structure. This tool offers new insight into how students construct mechanistic explanations of surface-liquid interactions. Collectively, this dissertation contributes to chemistry education research by advancing theoretical models of student cognition and demonstrating design principles for laboratory curricular instruction.

Author dc:creator

• Robert D Milligan (23291356)

• Chemistry, General
• Education, Sciences

Statement dc:rights

• In Copyright

DOI dc:identifier

https://doi.org/10.25417/uic.31451107.v1

OAI identifier oai:identifier

oai:figshare.com:article/31451107