• Journal of the Korean Chemical Society
• /
• v.47 no.2
• /
• pp.155-164
• /
• 2003

This study examined the types of explanations related to physical change and chemical change in the science textbooks of middle and high school based on the prior study of science teachers' understanding. For this research, the researchers analyzed 44 textbooks of middle school science and high school chemistry. As a result, there were no explanation or property type explanation represented in most of the textbooks related to physical and chemical change concepts. Also, there are few relationship represented between physical change and chemical change, and the examples related to physical change and chemical change were confused. These representations of textbooks can give rise to confusion of understanding of teachers and learners. So, it needs to re-design the explanation types correctly and constantly in science textbooks related to physical change and chemical change.

• Journal of the Korean Chemical Society
• /
• v.43 no.2
• /
• pp.213-224
• /
• 1999

Preconceptions of middle school students related to chemical change the students are surveyed. The students are divided into experimental group that are learned by concept change theory teaching model, and control group that are learned by traditional teaching method based on science textbooks. After the planned classes, the tendencies of concept change of the two groups according to students learning motivations are analyzed. New teaching methods, which based on concept change learning model and students learning motivations, developed by this research. And the effects of the new teaching method are testified. As a result, it is proved that most of the students have a lot of preconceptions, and persist the wrong conceptions after the classes. This tendency is same in the control group and in the experimental group.

• Journal of the Korean Chemical Society
• /
• v.48 no.1
• /
• pp.53-65
• /
• 2004

This study aimed to analyze the historical evolution of general ideas concerning the particles that represent matter properties and matter changes divided into physical change and chemical change. In the science historical viewpoint, the general ideas of the base that represent matter properties has been variously revised the 5types. The definition of the matter change have also changed the 3 types. From the analysis of the definitions in secondary school science textbooks and general chemistry textbooks, we found that a lot of confusion of eras in the contents that define the concepts. Sometimes, 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 7th science curriculum.

• Journal of the Korean Chemical Society
• /
• v.51 no.4
• /
• pp.365-374
• /
• 2007

The purpose of this study is to investigate the students' conceptions about the reaction rate changes during the chemical equilibrium shifts and also whether the questions about basic concepts of the reaction rate are helpful for the students' understanding of reaction rate changes during the chemical equilibrium shifts. The subjects were 100 students in the 12th grade. The questionnaires were composed of A, B, and A' set, which had to be answered sequentially. The A set consisted of questions asking the change of reaction rate when chemical equilibrium was shifted, the B set was to testify the basic concepts of the reaction rate, and the A' set was the same as the A set. The results showed that the students' understanding of the reverse reaction rate change was lower than that of the forward reaction rate change during the equilibrium shift. Also it was found that students' understanding of the reaction rate change caused by adding the reactant was fairly good while their understanding of the reaction rate change caused by temperature increment was very poor. Since the students marked very high scores in the B set questions, their poor understanding for the reaction rate changes during the equilibrium shifts was not seemed to be due to the lacks of the basic knowledge of reaction rate. Instead, it was due to the failure of applying the basic knowledge of reaction rate to the changes of reaction conditions. It was also found that the average scores of A' set were statistically higher than those of A set. It means the B set items were helpful for the students to solve the A' set items. These results evidenced the possibility of set questionnaires could help the students to connect the related concepts in solving the problems.

• Journal of The Korean Association For Science Education
• /
• v.19 no.1
• /
• pp.91-99
• /
• 1999

The researches related to students' preconceptions and conceptual change model have been reported that students' learning motivation is one of the key variable for the conceptual change. The effects of students learning motivations on conceptual changes were evaluated. Subjects of this study were 8th grade students. and they were divided into 2 groups. One group was taught by traditional teaching method, and the other group by concept change teaching model. After the intervention, learning motivations of the students were testified. The students of high motivation who were taught by concept change teaching model showed higher scores in the concept of chemical change than the students by traditional teaching method. But there was no difference in both groups of students who have low learning motivations. The learning motivations before the intervention. the motivations stimulated by classes. and the degree of concept understanding showed high correlation. The motivations stimulated by classes explain 23.3 % of the degree of concept understanding. The results seems to mean that students learning motivations contribute to the understanding of concepts. Especially confidence of learning as a subcategory of the learning motivation contributes significantly to the understanding of new concepts. In contrast, the traditional teaching methods and the teaching methods of concept change learning theory were not effective for the stimulation of students learning motivations.

• Journal of the Korean Chemical Society
• /
• v.54 no.5
• /
• pp.611-620
• /
• 2010

The purpose of this study was to explore the structure and content of chemistry teacher's explanations from the perspective of 'persuasion'. Especially, this study was to explore how the argument structure and the conceptual change constructs in chemistry teachers' explanations were established and interacted. Data were collected from chemistryI classes considering the gas unit which includes kinetic theory of gas, Graham's law, Boyle's law, and Charles' law. The classes were vediotaped and transcribed. The transcriptions were analyzed with Toulmin's argument frame and the two constructs of conceptual change model; the conceptual ecology and the status of a conception to interpret the persuasive structure and content of the teacher's explanations. As the results of this study, four explanatory discourses which show various persuasive explanations in chemistry classes. Based on this results, discussion and implications for effective teachers' explanations in chemistry classes were presented.

• Journal of the Korean Chemical Society
• /
• v.61 no.1
• /
• pp.34-44
• /
• 2017

The purpose of this study was to analyze the conception type change and to investigate the effect of understanding on concepts in electrochemistry after general chemistry lessons. The significant differences in concept understanding of electrochemistry were shown in both groups. Statistically significant gains in both groups were as shown in distinguishing the chemical cell, in identifying the anode and cathode, and in understanding current formation and flow, while, significant achievements in understanding the role of the salt bridge, and the need for a standard half-cell were not found. Taking elective chemistry II in high school had an effect on understanding related concepts of electrochemistry in general chemistry lessons. It was shown that many freshmen had difficulties in understanding exact related concepts in several kinds after general chemistry lessons. In order to solve these problems, it is necessary to teach contents of the basic concepts in electrochemistry exactly and to hold supplementary lessons.

• Journal of the Korean Chemical Society
• /
• v.43 no.4
• /
• pp.475-484
• /
• 1999

This study was to investigate the effective order of instruction for students learning the concepts of chemical change. Chemical change was considered as the important area in 8th grade chemistry part. The study consisted of 168 8th grade students, two classes of boys and girls each, from a middle school in Seoul. They were divided into two groups, the experimental group and the control group. The control group was taught in the order, which was presented in the science textbook; chemical change, atom, and molecule (CAM). For the experimental group, the order was molecule, atom, and chemical change (MAC). From the results of the study, there was a statistically significant difference between the control group and the experimental group. But the interviews indicated that the students were confused with the MAC method in spite of the effective learning. Therefore, for more effective concepts learning without a confusion, we need to provide our students with various learning sequences of science textbooks rather than fixed learning sequences.

• Journal of The Korean Association For Science Education
• /
• v.19 no.2
• /
• pp.305-314
• /
• 1999

The effects of three teaching models were compared in this research. One of those is concept change model, another is concept change model based on students learning motivations, the other is traditional teaching method based on science textbooks. The subjects of this research were the 8th grade students of Korean middle school. They were divided into three groups, and tested learning motivations. All of the three groups improved their learning motivations and concept understanding by the classes. Especially, the group of concept change model based on students learning motivations represented most effective improvement of learning motivations. The concept change teaching model and concept change teaching model based on students learning motivations are more effective in concept understanding than traditional teaching method based on textbooks. The students who have high learning motivations improved their concept understanding by the classes of concept change model based on students learning motivations. The students who have low learning motivations improved their learning motivations by the classes of concept change model based on students learning motivations also.

• Journal of the Korean Chemical Society
• /
• v.48 no.3
• /
• pp.291-299
• /
• 2004

The purpose of this study is to investigate views of high school students' learning of chemistry as one aspect of conceptual ecology. The results of this study will help us expand our understanding of conceptual change as it is used to evaluate learners. I made use of an interpretative research design based on principles of naturalistic inquiry. The participants in this study were six sophomore students. The picture of a chemistry class we draw from analyzing data is a play on stage with little interaction. Students accept passive and difficult-to-modify views of the learner roles that they should play in the chemistry classroom. Students identified chemistry classes as conservative places. 'Transmission' seems to remain the persistent and dominant classroom cultural dynamic for both the teaching and learning of chemistry. Students should understand about learning processes, and how to play, monitor, evaluate and regulate them. Students should experience the plausibility and fruitfulness of learning chemistry, and it will help students to feel a "love of learning chemistry." As students change their views of learning chemistry, it will help to improve their learning and to experience conceptual change in chemistry learning.