A cross-age study of students' understanding of basic Inorganic Chemistry qualitative analysis

Year: 2001

Author: Tan, Kim Chwee Daniel

Type of paper: Abstract refereed

This cross-age study sought to determine the extent of secondary students’ (14-17 years old), junior college students’ (16 to19 years old), and graduate in-service teachers and trainee-teachers’ understanding and alternative conceptions of basic inorganic chemistry qualitative analysis. The results from the administration of the two-tier multiple choice Qualitative Analysis Diagnostic Instrument (QADI) showed that there was a statistically significant difference in mean scores across educational levels – as expected, the in-service teachers and trainee-teachers obtained the best results, followed by the junior college and the secondary students. However, the mean scores of the graduates (9.9/19), junior college students (8.1) and secondary students (5.8) showed that they found the QADI difficult. The cross-age study showed that many alternative conceptions were prevalent among the different groups but were consistently held by only a small number of subjects (0-23%) across all contexts examined in the QADI. These results indicated that the subjects might have more than one conception for a particular concept, or had little understanding of qualitative analysis and resorted to guesswork. The present chemistry practical assessment system in which only students’ written reports are assessed and marks mainly allocated to correct observations could be the major factor influencing students’ lack of understanding of QA.