| Summary: | 碩士 === 國立臺灣師範大學 === 科學教育研究所 === 90 === The present study is a Repertory Grid Technique(RGT) application. 9th grade students’ misconception in electrochemistry is chosen as the topic. In order to develop the instrument, a construct eliciting questionnaire has been done by 117 pupils. Cronbach αof the instrument is 0.94. Twenty-two volunteer students of Taipei county completed the grid evaluation, while 13 students with stable conceptions were interviewed. Distinction and comparison between expert pupils and novices were made. The major findings of misconceptions in electrochemistry are list as follows:
1. Electrons flow from negitive electrode through aqueous solution to positive electrode. Negitive electrode loses electrons and positive electrode gains electrons in the electrolysis reaction.
2. In electrolysis of water, there was no visible solid atom produced . So there was no loss or gain of electron.
3. Neglecting to refer to position of circuit, pupils fail to answer with the representation of question. It made them have a wrong judgement on the direction of electron flow.
4. The electric current was only the result of the movement of electrons, not the moving of the ions.
5. Refering to the influence of language, anion should move to positive electrode.
6. Electroneutrality means “Number of anion and number of cation are equal. ”
7. The function of a salt bridge was as a conjunction between two electrolysis cells, not as a source of supplying ions.
8. In electrolysis of water, gas produced made electrodes lose weight.
9. In electrolysis of copper sulfate solution, with carbon electrodes or copper electrodes made no differences.
Some of the misconceptions are found cross-situations, the others are not.
There are some critical differences between pupil experts and pupil novices. The pupil experts have well-organized concept and better microscopic-view. The Novice has poor concept connection and macroscopic-view.
At last, some suggestions of science teaching and further research are proposed.
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