• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.454-465
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• 2015

The goal of this study is to investigate pre-service chemistry teachers’ understanding of the boiling process of a liquid mixture. We surveyed 65 students in the chemistry program of the College of Education about the boiling point of a 50%(by mole) ethanol aqueous solution and the temperature changes during heating. We then interviewed 9 of these students. According to the survey results, the percent of the pre-service teachers who thought that the boiling point of the ethanol solution would be ‘between the boiling points of ethanol and water (78-100 ℃)’ and ‘the same as that of ethanol’ were 52.3% and 35.4%, respectively. The majority of those who stated the former explained that the boiling point of the ethanol solution increased due to the effects of attraction or blocking by water molecules. Most of those who believed the latter explained that physical properties such as the boiling point would not be changed by the addition of water. With regard to the temperature change during heating, 69.2% of the teachers thought that the temperature would increase gradually while boiling, which some thought resulted from the increasing amount of water in the solution as the ethanol boiled off. Others thought that two temperature plateaus would be observed as each component of the liquid mixture underwent phase transition at its specific boiling point. When asked about the particle model of the gas phase during the boiling and evaporation process, some students drew both ethanol and water during evaporation but only ethanol when boiling. We discussed several alternative concepts of pre-service chemistry teachers about the boiling process of liquid mixtures and ways to improve their understanding.

• Journal of Science Education
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• v.47 no.1
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• pp.24-36
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• 2023

In this study, we investigated chemistry teachers' the Stage of Concern (SoC) and the Level of Use (LoU) regarding competency assessment, which was emphasized along with the introduction of the 2015 revised curriculum. A questionnaire was developed based on the CBAM, and responses from 123 chemistry teachers were analyzed. The frequency was investigated for both SoC and LoU, and then the chi-square test was performed according to demographic variables. As a result of the SoC analysis, most of the teachers stayed in stage 3 (management concern, 26.8%) and stage 2 (personal concern, 19.5%). Additionally, among the demographic variables, there was a statistically significant difference in whether or not related education experience was present during the pre-service teacher period. In LoU analysis, Level III (mechanical) was the most frequent (26.8%), followed by Level I (orientation, 22.8%), Level II (preparation, 13.8%). In LoU, there was also a statistically significant difference in whether or not related education experience was present during the pre-service teacher period. The Spearman correlation coefficient between SoC and LoU in the competency assessment was .298 and there was a positive correlation. Based on the above results, educational implications for improving the concern and use of chemistry teachers for competency assessment were discussed.

• Journal of the Korean Chemical Society
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• v.66 no.3
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• pp.228-242
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• 2022

In this study, the educational effect was investigated by providing a teaching program so that pre-service chemistry teachers could apply model ignorance education to teacher training practice. The teaching program was constructed in consideration of the sensemaking concept proposed in the study of Odden & Russ and the process of teacher sensemaking proposed by Asli et al. The subjects of this study were 23 pre-service teachers in the 4th year of chemistry education department at a teacher training university in the central region of Korea. In order to form a sensemaking for the model's ignorance education, the teaching program consisted of four stages; the initial idea generation stage, cognition of model's ignorance stage in a inconsistent situation, the lesson strategy construction stage for model ignorance education, and lesson plan & practice stage during teacher training practice. In the first stage of this program, pre-service teachers' initial ideas about the Arrhenius model and Bronsted-Lowry model of acid-base reaction, and the electron transfer model of the oxidation-reduction reaction were investigated. In the second stage, inconsistant situation that cannot be explained by the knowledge of model was presented to recognize the ignorance of the model. The third stage was to develop the teaching ability of model's ignorance through textbook analysis and lesson strategy composition activities. As a final stage, during the teacher training practice, the pre-service teachers were asked to plan and practice the implementation of the model's ignorance education. Through the teaching program to form a sensemaking for ignorance education of the models, pre-service teachers had come to recognize the ignorance of the model, acquired ability to organize and execute lesson strategies reflecting model ignorance, and acquired recognition of the educational value and necessity of teaching the ignorance of models.

• Journal of The Korean Association For Science Education
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• v.27 no.2
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• pp.144-152
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• 2007

In this study, high school science teachers' and students' various conceptions related to osmosis phenomena were compared with and analyzed in relation to the content of science textbooks used in high school science classrooms and college science courses. The questionnaires developed by the researchers were administered to science teachers and students. Differences can be found between the explanations of science textbooks on osmotic pressure and semi-permeable membranes. Many science teachers and students thought of osmotic pressure as 'membrane pressure occurred by the movement of a solvent'. Moreover, the types of teachers of semi-permeable membranes were similar regardless of their academic majors. Many of the teachers thought of a semi-permeable membrane as a membrane that 'passes small-size particles'; however, many students thought of this type of membrane as being 'selectively permeable'. Also, the salt-pickling cabbage phenomenon seemed to cause significant confusion to science teachers and students. These study results show that teachers and students possess various conceptions related to the osmosis phenomena. These different conceptions related to osmosis phenomena might cause confusion and diverse conceptions including misconceptions among teachers and students.

• Journal of the Korean Chemical Society
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• v.49 no.5
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• pp.503-512
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• 2005

• Journal of the Korean Chemical Society
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• v.62 no.6
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• pp.441-452
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• 2018

This study investigated mentor teachers' mentoring types and how the types of mentoring changed throughout the collaborative mentoring program for beginning science teachers who had difficulties in teaching practice. One-on-one mentoring meetings were audio-taped and transcribed for analysis. The result of the study showed that mentors took various roles such as Observer, Critical friend, Provider of feedback, Instructor, Role model, Evaluator, Counselor, and Equal partner. However, if mentoring did not bring about a change in the perception of a science instruction of a mentee teacher, there was no positive change in the teaching of the mentee teacher. Therefore, mentor teacher must have enough time to concretely discuss about mentee teachers' perception of a science instruction, mentoring method, etc. with mentee teacher before mentoring.

• Journal of the Korean Chemical Society
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• v.59 no.4
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• pp.289-295
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• 2015

The purpose of this study was to survey the elementary school teachers' thoughts of the classification criteria for evaporation and boiling concept in the heating and non-heating conditions. For this purpose, we conducted a survey and interviews with 37 elementary school teachers. When the heating conditions were presented, many teachers thought evaporation phenomena as boiling. In opposite condition, many teachers thought boiling phenomena as evaporation. This means that teachers‘ thought of boiling phenomena was connected with heating conditions and evaporation phenomena with non-heating conditions. In addition, the classification criteria to distinguish evaporation and boiling phenomena depending on the heating and non-heating conditions were not coherent. In this study, we suggested that a various cases beyond the typical case must be presented in the textbooks and teaching in order to avoid confusion of thoughts related to evaporation and boiling concepts.

• Journal of the Korean Chemical Society
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• v.46 no.3
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• pp.252-264
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• 2002

In this study, the experimental apparatus for boiling point and melting point in science textbooks of various curriculums were analyzed. Science teachers' views on the difference between the experimental value and the value written in textbooks were inquired, too. Their views on the experimental apparatus, nd results of freezing point,melting point, boiling point, fractional distillation, and thermometer calibration were also investigated. The results of this study showed that the types of experimental apparatus for boiling point and melting point were somewhat dif-ferent with science textbooks and curriculum. The teachers' views were also various according to their background. In the experiment of the fractional distillat ion, a large number of teachers recognized mismatch between the exper-imental value and the value written in textbooks as mistake of textbook contents or problem of experiment itself. The teachers of chemistry background take higher recognition of the requirement of thermometer calibration than those of non-chemistry background in middle school.

• Journal of the Korean Chemical Society
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• v.68 no.5
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• pp.287-298
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• 2024

In this study, the planning and usage of questioning by the types of questions of sixty-six science teachers were investigated. The analyses of the results indicated that the levels of planning and the anticipation of student responses were differed by the types of questions. However, even if student responses were anticipated, feedbacks or follow-up questions were not planned. The ways to ask answers were found to be differed by the types of questions. The usage frequencies of the types of questions were differed depending on the types of lessons and constructivist perceptions. Student factors were considered as obstacles to effective questioning. Based on the results, some ways to improve science teachers' ability to use questioning effective were discussed.

• Journal of the Korean Chemical Society
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• v.49 no.3
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• pp.300-310
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• 2005