Linking the Macroscopic, Sub-microscopic and Symbolic Levels: The Case of Inorganic Qualitative Analysis

Basic Grade 10 inorganic qualitative analysis in Singapore requires students to carry out procedures using chemicals, apparatus and appropriate techniques for which they record their observations and make inferences based on the observations. As students are assessed mainly on their written observations, they focus on getting the correct results and writing ‘standard’ observations. Thus, many students merely follow instructions given in the worksheet and seldom think about or understand the reactions involved especially in terms of what is occurring in these reactions at the sub-microscopic level. To respond to this situation, the authors first designed the Qualitative Analysis Diagnostic Instrument to identify students’ understanding of the reactions involved in qualitative analysis. Secondly, the authors developed the Qualitative Analysis Teaching Package to help students learn qualitative analysis by facilitating their understanding of the sub-microscopic and symbolic level explanations of the macroscopic level experiences of the procedures and reactions involved, as well as the manipulative, observational and inferential skills and thinking processes required. The diagnostic instrument and teaching package are especially important with the imminent change from the current one-off national practical examination to school-based assessment in 2008 with the focus on manipulative, observational, analytical and planning skills.