First-year University Students’ Experiences in Learning Threshold Concepts of Acids-Bases Chemistry

This paper interrogates the concept of threshold concepts (TCs) of acids-bases in the teaching and learning of general chemistry of first-year university students. Acids-bases chemistry has been identified by chemistry scholars worldwide as one of the threshold concepts (TCs) in chemistry that seems to be difficult and the culprit of most failures in chemistry. Acids-bases reactions are also central to learning of other chemical reactions within the discipline of chemistry and other science concepts in life sciences (biology) and physics. The paper is based on the challenges students experience in general chemistry, which tend to discourage students from studying chemistry or pursuing their studies in chemistry-oriented professions, such as medicine, engineering, agriculture, natural resources, and chemistry education; or responsible for students dropping out of the university education completely. To address this problem, we explored lecturers’ and students’ challenges that students experience in learning TCs of acids-bases chemistry and the students’ perspectives of chemistry. A qualitative research methodology was employed in the study. Data was collected through classroom observations and student focus-group conversations. A thematic approach was employed to analyse data. Five chemistry educators and their classes were purposely sampled. Vygotsky’s social cognitive development theory was used as a theoretical framework to understand the teaching-learning of acids-bases chemistry. Findings suggested that some students’ experiences transformed them into self-directed learners. Researchers can investigate other avenues to the portal in teaching-learning TCs.