Beyond VSEPR─The Significance of p-Orbital Conjugation in Determining the Hybridization

General chemistry is a foundational course designed, in part, to prepare students for organic chemistry and subsequent advanced chemistry courses. Models introduced in general chemistry, such as Lewis structures, resonance, and hybridization, are reiterated throughout the chemistry curriculum. This article compares explanations and end-of-chapter textbook problems related to hybridization from eight general chemistry textbooks. Subsequently, it compares these findings by introducing and discussing hybridization and p-orbital conjugation in eight organic chemistry textbooks. The study aimed to assess whether general chemistry textbook explanations align with organic chemistry explanations and promote the development of representational competence for hybridization and conjugation models. The findings show that all eight general chemistry textbooks use a simplified electron domain counting (EDC) technique to find hybridization regardless of whether resonance and p-orbital conjugation are or are not possible in chemical structures. This simplification will require recalibration of the hybridization model to fully understand organic structure and reactivity. Additionally, most organic chemistry textbooks do not explicitly connect hybridization and resonance in introductory sections. This can present challenges, particularly if organic instructors couple concepts of hybridization and conjugation with earlier units such as acid-base chemistry.

Duke Scholars

Author Charlie T. Cox Chemistry