• Journal of the Korean Chemical Society
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• v.52 no.5
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• pp.561-568
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• 2008

• Journal of the Korean Chemical Society
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• v.60 no.1
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• pp.48-58
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• 2016

This study was to investigate the types of middle school students’ conceptual change on electrolyte and ion. Data were collected by pre- and post- exams of 9th grade students’ conceptions of electrolyte and ion, and by semi-structured interviews with nine students served as case representatives who participated in the study. All interviews were transcribed, analyzed and classified by conceptual change according to the responses of the students. The results are as follows: First, students’ ion conceptual change was classified into four types; simple conception to sophisticated conception, incomplete conception to scientific conception, misconception to confused conception, and misconception to misconception. Most students had difficulty in understanding of the concepts of ion in pre- and post-class, and they failed to distinguish between atom and subatomic particles precisely. Second, students’ conceptual change of electrolyte was also classified into the following four types; partially scientific conception to sophisticated conception, misconception to partial misconception, incomplete conception to incomplete conception and misconception to misconception. The study found that students had difficulty distinguishing the difference between electrolytes and nonelectrolytes. Third, students also had difficulty understanding the concepts on particles because they learned the ‘electrolyte and ion’ unit so quickly in the second semester of 9th grade in order to fill in the academic reports for applying high schools. Furthermore, some suggestions were made based on the results for understanding scientific concepts on particles.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.83-89
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• 2002

In this study, students' responses to anomalous data in studying ‘density' were analyzed, and the relationships among trait/state self-regulation strategies, the degree of cognitive conflict, and conceptual change were examined. A trait self-regulation strategy test, a preconception test, and a test of response to anomalous data were administered to 352 eighth graders. Among them, 146 students whose preconceptions were consistent with the presented initial theory were selected. After they had read a scientific explanation, a state self-regulation test and a researcher-made conception test were administerd. There were no significant correlations among the subcategory scores of trait/state self-regulation strategies and the degree of cognitive conflict. The scores of the conception test were significantly correlated with those of trait planning, trait effort, state planning, state self-monitoring, and state effort. State effort was only a significant predictor on students' conceptual change.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.84-95
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• 2008

In this study, preconceptions held by chemistry major secondary school science teachers were searched in relation to explanations of water evaporation phenomena with phase equilibrium diagrams. 25 chemistry major science teachers were selected to complete questionnaires developed in this study and 6 among of them were selected to participate in follow-up interviews. Among these, 10 participants were selected for an evaluation of the change of their preconceptions through lessons developed in this study. From the results, it was found that many teachers believed that the phase equilibrium diagram could not explain water evaporation phenomena. They also thought that there was no relation between vapor pressure and the vertical axis of the phase equilibrium diagram. However, after the lessons in earth science, they recognized that the vapor pressure curve of the phase equilibrium diagram could be explained by adopting a saturated vapor curve. Because they had known the process of application the conceptions of saturated situation, nonsaturated situation, process of equilibrium movement in saturated vapor curve. They could understand natural phenomena such as evaporation with the phase equilibrium diagram through a change in their conceptions as guided from science lessons integrating earth science and chemistry.

• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.56-64
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• 2007

This study examined the influences of cognitive conflict and anxiety induced by a discrepant event and an alternative hypothesis, attention, and effort on conceptual change. Two hundred three students having misconceptions about density were selected from 462 seventh graders based on the results of a preconception test. Tests of cognitive responses and anxiety to a discrepant event were administered before and after presenting an alternative hypothesis. Computer-assisted instruction (CAI) was then provided to students as a conceptual change intervention. Tests assessing attention and effort allocated to the CAI, and conceptual understanding were administered as posttests. Cognitive conflict induced by a discrepant event was found to increase after presenting an alternative hypothesis. Pre-cognitive conflict induced by only a discrepant event exerted a direct effect on post-cognitive conflict induced by a discrepant event and an alternative hypothesis. Post-cognitive conflict had a direct effect on conceptual change. Pre-anxiety decreased after presenting an alternative hypothesis. Pre-anxiety influenced post-anxiety, and this influenced on conceptual change via effort negatively. Attention had a direct effect as well as an indirect effect on conceptual change via effort. These results suggest that the strategy presenting both a discrepant event and an alternative hypothesis to students in concept learning could facilitate conceptual change by inducing more cognitive conflict or active participation of students through the decrease of anxiety than that presenting a discrepant event only.

• Journal of the Korean Chemical Society
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• v.45 no.6
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• pp.589-594
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• 2001

In this study, the effects of the number and the presentational type of anomalous data on students'cognitive conflict and conceptual change in studying 'conservation of mass before and after combustion'were investigated. The subjects were 128 eighth graders in a co-ed middle school. A preconception test, a test of response to anomalous data, and a conception test were administered. Four types of anomalous data varying the number (one/two) and the presentational type (text/text+figure) were presented. The results indicated that students with two anomalous data showed more cognitive conflicts than those with one. However, no significant differences in the degree of cognitive conflict were found by the presentational types of anomalous data. The ANOVA results indicated that there were no significant differences by the characteristics of anomalous data in the conception test scores.

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.357-369
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• 2001

This study aimed to analyze the evolution of general ideas concerning the element and the atom. In the scientific viewpoint, the modern idea of the element has been variously revised by the ancient Greeks, Boyle-Lavoisier, and Dalton. The definition of the atom was confused with that of the element from the ancient Greecian era to Lavoisier's era. The definition was also changed by Dalton and Rutherford. An analysis of the definitions of element and atom as presented in science textbooks for secondary school students and in general chemistry textbooks revealed that these definitions from diverse eras are confusing and inadequately explicated. The definition presented in one textbook was contradictory to the definitions in other textbooks. This tendency has been sustained in the textbooks from the 4th to 6th science curriculum. Therefore, we need to clarify the definitions of element and atom in order to help the students gain a better understanding of these scientific concepts.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.110-118
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• 1999

In this study, the instructional influences of the conceptual change model based on the cognitive conflict and the conceptual change model emphasizing the social consensus were investigated. The subjects were 109 7th-graders in a boys' middle school in Seoul, and were taught about the changes of states, density, and dissolution for 8 class periods. The hypotheses provided in the instructions were constructed from the results of a pilot test. Prior to the instructions, three tests regarding the perceptions of discussion, the attitudes toward science instructions, and the perceptions of participation were administered. Two types of the conceptual change instructions and the traditional instruction were used in the treatment groups and the control group, respectively. After the instructions, the students' achievement, the conceptions, the perceptions of discussion, the attitudes toward science instructions, and the perceptions of participation were investigated. ANCOVA results revealed that the scores of the treatment groups were significantly higher than those of the control group in the achievement test. Although the score of the treatment group using the conceptual change model emphasizing social consensus were higher than those of other groups in the conceptions test, the differences were not statistically significant. The perceptions of discussion were significantly more positive in the treatment group using the conceptual change model emphasizing social consensus than in the control group. However, there were no significant differences in the scores of the attitudes toward science class and the perceptions of participation among the three groups. Educational implications are discussed.

• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.65-72
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• 2007

The purpose of this study was to examine the 7th national science curriculum (chemistry domain) regarding the meanings of ‘mulgil' (Korean), the particulate nature of matter, and the state of matter. It was found that the term of ‘mulgil' was being used vaguely as representing material, matter, or substance without clear definition. This was problematic by reason that it could hinder students from having the concept of substance. Regarding the particulate nature of matter, molecule was introduced as a basic unit of matter at grade 7, prior to atom and ion, which were introduced at grade 9 and 10, respectively. It is necessary to reconsider the sequence of each particle concept to provide students with more consistent and comprehensive understanding of structure of matter. In the case of change of state, key concepts such as conservation of matter or reversibility were omitted in the curriculum document, and explanations based on various aspects of particles were somewhat insufficient. The concept of matter is fundamental to chemistry, and we must recognize it as a concept that needs to be taught clearly. Implications for curriculum revision were discussed.

• Journal of the Korean Chemical Society
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• v.53 no.4
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• pp.445-452
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• 2009

In this study, the influences of the context of discrepant events on the conceptual change process using cognitive conflict strategy were investigated in terms of students' cognitive and motivational variables such as cognitive conflict, situational interest, attention, effort, conceptual understanding. A preconception test was administered to 536 seventh graders. A test of response to a discrepant event and a situational interest questionnaire were then administered. The context of discrepant events, either scientific or everyday, was randomly presented to the subjects. After learning the concept of density, the tests of attention, effort, and conceptual understanding were administered. The reponses of 194 students who had been found to possess the target misconception were analyzed. The results revealed that the scientific-context discrepant event induced higher cognitive conflict than everyday-context one. The context of discrepant events, however, did not show significant correlations with situational interest, attention, effort, and/or conceptual understanding. The result of path analysis indicated that the context of discrepant events both directly influenced cognitive conflict and indirectly influenced conceptual understanding via cognitive conflict.