Types of Middle School Students' Conceptual Change on the Concept of Electrolyte and Ion

摘要

This study was to investigate the types of middle school students?ˉ conceptual change on electrolyte and ion. Data were collected by pre- and post- exams of 9th grade students?ˉ conceptions of electrolyte and ion, and by semi-structured interviews with nine students served as case representatives who participated in the study. All interviews were transcribed, analyzed and classified by conceptual change according to the responses of the students. The results are as follows: First, students?ˉ ion conceptual change was classified into four types; simple conception to sophisticated conception, incomplete conception to scientific conception, misconception to confused conception, and misconception to misconception. Most students had difficulty in understanding of the concepts of ion in pre- and post-class, and they failed to distinguish between atom and subatomic particles precisely. Second, students?ˉ conceptual change of electrolyte was also classified into the following four types; partially scientific conception to sophisticated conception, misconception to partial misconception, incomplete conception to incomplete conception and misconception to misconception. The study found that students had difficulty distinguishing the difference between electrolytes and nonelectrolytes. Third, students also had difficulty understanding the concepts on particles because they learned the ??electrolyte and ion?ˉ unit so quickly in the second semester of 9th grade in order to fill in the academic reports for applying high schools. Furthermore, some suggestions were made based on the results for understanding scientific concepts on particles.