Uncovering Instructors and Graduate Teaching Assistants Topic-Specific Pedagogical Content Knowledge (TS-PCK) of Precipitation Reactions and Solubility Rules

Pallavi Nayyar

Scott E. Lewis

University of South Florida

This study investigated general chemistry instructors’ and teaching assistants’ topic-specific Pedagogical Content Knowledge (PCK) pertaining to precipitation reactions and solubility rules. General chemistry lectures emphasize conceptual understanding of precipitation reactions through symbolic and sub-microscopic representations, while labs apply these principles for qualitative and quantitative analysis of inorganic salts, offering students a macroscopic view. Drawing upon the framework of PCK, which integrates content knowledge, pedagogical knowledge, and knowledge of students’ understanding, this study explored how instructors and graduate teaching assistants (GTAs) conceptualize, teach, and assess this topic in their teaching context. Data were collected through semi-structured interviews with instructors and GTAs and analyzed using thematic analysis focusing on components of TS-PCK. Thematic analysis provided insights into the similarities and differences in PCK within and between instructors and GTAs, as well as the factors influencing their teaching practices. The study contributes to understanding the collective PCK of instructors and GTAs at a topic-specific level and has implications to leverage their combined expertise to promote students’ understanding at the three integrated levels- symbolic, sub-microscopic and macroscopic.