Search

General spectroscopy is known to be difficult for novice students due to its complex and abstract nature. In this study we used a first-year chemistry Mini Spec laboratory activity to uncover language barriers to student learning in spectroscopy. Analysis revealed that language barriers generated conceptual difficulties for English as Second Language (ESL) students. As well as demonstrating difficulty with understanding of the origin of spectral lines identified in prior research, this work surfaces previously unreported language difficulties which were characterized in terms of technical and non-technical language. These include observations that 'refract' and 'diffract' appeared poorly delineated for students, the teleological animism of 'jump' to describe excited electron transitions towards the ground state, and the non-technical term 'discrete' being difficult for students to understand and construct meaning for. In addition to this, students battled with the symbolic language required to depict the formation of spectral lines. Several solutions to the language difficulty are proposed including the re-sequencing of macroscopic, sub-microscopic and symbolic teaching and reconsidering the usefulness of certain non-technical terms for teaching and learning spectroscopy.

Laboratory work in chemistry has been extensively researched in the last decade but the gap between research and practice is still broad. This "Perspective" shares 10 guiding principles relating to university laboratory education, drawing on research over the last decade. Written with an audience of practitioners in mind, the "Perspective" aligns with Hounsell and Hounsell's congruence framework, so that the 10 principles consider all aspects of the laboratory curriculum: design, teaching approaches, and assessment approaches as suggested by Biggs, but additional contextual factors relating to teaching context: backgrounds of students and their support, and overall laboratory organisation and management. After discussing the rationale for each guiding principle, examples of approaches are given from recent literature along with prompts to help enact the guiding principle in practice.

Central to conceptual understanding of STEM disciplines is visuospatial processing. Despite its acknowledged role in assuring learners' success, less is known about the underlying reasoning students must employ when solving 3-D problems and the ways in which gaining an understanding of this can inform formative assessment and learning in STEM education. Chemists must utilise their spatial understanding when visualising 3-D structures and processes from 2-D representations and so this exploratory practitioner-researcher study sought to identify the ways in which secondary school chemistry students reason when explaining their predictions about molecular geometry, and how the use of certain modalities was linked to assessed accuracy. Coding of students' verbal and written responses to the research task revealed that students employed multiple reasoning strategies and conceptual resources to facilitate use of analytical heuristics and imagistic reasoning. Analysis of students' verbal responses and spontaneous gestures provided insight into the extent of imagistic vs. analytical reasoning and the finergrained conditions which promoted their use. Importantly, it was observed that despite being instructed on the use of VSEPR theory to find analytical solutions, some students exhibited preference for alternative reasoning strategies drawing upon imagistic reasoning; showing more nuanced and varying degrees of accuracy through their verbal responses and representations gestured in 3D space. This work has pedagogical implications as use of specific reasoning strategies and the identification of key conceptual resources is not readily promoted as classroom practice for learning or assessment. This study therefore raises questions and contributes to the evidence base for attending to learners' visuospatial thinking, as revealed through the multiple modalities they may use to assist and communicate their understanding, and highlights the significance of this to formative assessment in Chemistry and STEM Education.

The laboratory is a complex environment where the three levels of the chemistry triplet coincide. As the laboratory environment places a large demand on the working memory of students, cognitive load theory can address overload which causes barriers to learning. Breaking down barriers requires iterative phases of analysis/exploration, design/construction and evaluation/reflection over multiple cycles which are the hallmarks of design-based research. In a complex setting, managing change and redressing teaching approaches can be difficult to navigate. Design-based research incorporates iterative phases in which theory informs decision making. This paper uses the context of a laboratory exercise of emission spectra to illustrate how the cognitive load theory can be used in tandem with design-based research to support student learning in the exercise. Using this approach, it was possible to show how barriers to student understanding, including task demands and conceptual demands were supported through proposed approaches focusing on extraneous, intrinsic and ultimately germane cognitive load.