Prediction! The VSEPR Game: Using Cards and Molecular Model Building To Actively Enhance Students’ Understanding of Molecular Geometry

Abstract

Previous work has shown that the formation of misconceptions remains one of the most significant barriers to progress for chemistry students. Determination and visualization of the shapes of molecules using valence shell electron pair repulsion theory (VSEPR theory) is an example of an abstract concept that students often find difficult to learn. Concepts may be better understood if the learning process were supported by innovative, interactive, learning resources. In order to address the conceptual difficulties that students may encounter when using VSEPR theory, an activity has been developed that is supported by simple molecular models. Activity cards give students the opportunity to work through the steps required to predict the shape of a molecule in an engaging manner that promotes social learning. Students were tested before and after the activity. A statistically significant improvement in scores (p = 0.001) was found, which indicates that the activity cards and molecular models could help students understand the topic.

The role of visuospatial thinking in students’ predictions of molecular geometry

“…This paper will therefore seek to identify and describe how and when students use imagistic or analytical reasoning when making pen-on-paper predictions about molecular geometry and examine whether specific reasoning strategies promote greater accuracy in these predictions. Molecular geometry is a key chemistry context to investigate spatial reasoning due to it being a core skill that all chemistry students (at senior school and undergraduate levels) must acquire and understanding this abstract concept is key to comprehending a wide range of scientific topics; such as the structure and function of biomolecules, industrial catalysts, synthetic polymer engineering and quantum mechanics, spanning across several STEM disciplines (Nicoll, 2001;Erlina et al, 2018). To relate, represent and predict molecules' submicroscopic form is difficult for learners; it requires imagining how the molecules will appear from different perspectives and as such is certainly aided by the ability to visualise and mentally manipulate (Vlacholia et al, 2017).…”

“…To relate, represent and predict molecules' submicroscopic form is difficult for learners; it requires imagining how the molecules will appear from different perspectives and as such is certainly aided by the ability to visualise and mentally manipulate (Vlacholia et al, 2017). Similarly, students have been shown to have difficulty with determination of molecular geometries using the established Valence Shell Electron Pair Repulsion Theory (VSEPR theory), commonly taught in schools and universities (Furio et al, 1996;Gillespie, 1997;Nicoll, 2001;Erlina et al, 2018).…”

Visualizing molecular structures and shapes: a comparison of virtual reality, computer simulation, and traditional modeling

“…Physical models are low tech and relatively inexpensive. The use of this tool is well documented in the chemistry education literature (Erlina, Cane, & Williams, 2018;Jones, 2001;Pfennig & Frock, 1999). They are useful for representing simple molecules; however, their utility for the representation of molecules is limited.…”

Valence‐Shell Electron‐Pair Repulsion Theory Revisited: An Explanation for Core Polarization

“…[5,6] Hence,i tc onstitutes, in conjunction with other models, such as Lewis structuresa nd electronegativity,abasic pillar of "chemical intuition" and structural analysis in chemistry. [7,8] When developing the concepts behind VSEPR, the repulsion betweenelectron pairs was used to explain the organization of the valence ligandsa nd lone pairs. However,a si ts name states, this theory is generallya ppliedt ot he valence shell, and less attention has been paid to the core electrons.…”

“…This theory has proven to work well for main‐group‐based systems, with only some exceptions, especially for complexes bearing a d 0 central atom . Hence, it constitutes, in conjunction with other models, such as Lewis structures and electronegativity, a basic pillar of “chemical intuition” and structural analysis in chemistry …”