Author: Chiu, Mei-Hung, Fu, Hwa-Wen
Type of paper: Abstract refereed
This study focuses on understanding how students solve problems in stereochemistry (i.e., decide the isomer type of a compound). In particular, how students solve problems with different representations of moleculars, and the ideosyncratics of their problem-solving strategies. Subjects were individually monitored by the researcher using a thinking-aloud method. With this method subjects were given tasks and asked to describe howÿ they are solving the task. The data consist of a transcript of each problem-solving session and written work the subject produced. All the sessions were audiotaped and videotaped for later transcription and analysis. The finding suggests that on average, the successful students outperformed the non-successful students on all four types of questions (namely chemical formula (Type I), 2-D (Types II) & 3-D representations (Type III) and real molecular models (Type IV)). Surprisingly, the biggest difference between the successful students and non-successful students was on Type II which is included a cyclic chemical compound to increase the complexity of the problem situation. Even though this item was tested, we found that the successful students were able to transform a 2-D representation to multiple useful representations to solve the problem, whereas the non- successful students were unable to 'visualize' the problem from different perspective. The smallest difference was on Type IV which provided the students with concrete models for solving problems. This finding suggests that most students were beneficial from using 3-D models. We also found that the successful students were able to 'see' the similarities between questions and applied their problem solving strategies back and forth, whereas the non-successful students considered each questions in isolation.