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| Type |
Poster Presentation |
| Area |
Chemistry Education |
| Room No. |
Grand Ballroom |
| Time |
10월 18일 (목요일) 11:00~12:30 |
| Code |
EDU.P-490 |
| Subject |
Analysis of Textbooks on Electrolysis Experiments of Electrolyte Aqueous Solution and Conclusions on Electrolytic Electrolysis of Gifted Students |
| Authors |
Kihyang Kim, Seounghey Paik1,*
Chemistry, Sejong Academy of Science and Art, Korea
1Department of Chemical Education, Korea National University of Education, Korea
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| Abstract |
Electrolysis of electrolytic aqueous solution produced H2 and O2 at the (-) and (+) poles, which is an experiment that revealed that water is not an element but a compound. In addition, electrolysis of aqueous solutions is presented as a different motivation in different units of various subjects. In this regard, we analyzed eight middle school textbooks, four kinds of chemistry I, and four kinds of chemistry Ⅱ. The questionnaires were asked to students of gifted students about the relationship between electrolytic phenomena and electrolysis phenomena. In addition, students were asked to analyze the results of electrolysis experiments of aqueous solutions and their interpretations. In Science 2, experiments were carried out in the same manner as electrolysis of electrolytic aqueous solution to explain the principle of current flow in aqueous electrolyte solution. However, only the movement of ions was concerned and the presence of water and the electrolysis process at each electrode were omitted. As a result of analyzing 8 textbooks, only one kind of textbook and teacher 's guidebook mention the possibility of electrolysis of aqueous solution. Of the students who responded to the questionnaire, 45% of the students explained the current flow in the electrolytic aqueous solution as a consumptive model that considers ion migration only. Electrolysis experiments of electrolytic aqueous solutions are handled twice in the same unit with different motions. Nevertheless, it can be interpreted that the opportunity to look at the phenomenon as a whole is not provided because of focusing on each learning objective. In order to explain that electrons are involved in chemical bonding in Chemistry I, the textbook presents electrolysis experiments of NaOH (aq) and Na2SO4 (aq), and exploration experiments to confirm that the volume ratio of hydrogen and oxygen produced is 2:1. Two kinds of chemical Ⅰ guidebooks, three kinds of chemical Ⅱ textbooks, and four kinds of teacher guidebooks list the kinds of ions that are less oxidizable and less reducible than water considering only the standard reduction potentials, and present the expected experimental results uniformly. In addition, it ignores the role of electrolytes in all chemistry Ⅱ textbooks and teacher guides, and suggests a kind of unified mechanism in which water molecules are directly electrolyzed from both electrodes. As to the different electrolysis results of NaOH (aq), Na2SO4 (aq), and KNO3 (aq), the students interpreted that the product was dissolved in water rather than attempting a bold interpretation that different kinds of products were produced at the electrode Or interpreted as experimental error.This can be interpreted as indirect evidence that students are accepting textbook descriptions truthfully because of a uniform science description. |
| E-mail |
kihyang262@naver.com |
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122nd General Meeting of the KCS