• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1385-1402
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• 2013

This study analyzes pre-service teachers' PCK dealing with visualization of the contents related to boiling point elevation and teaching methods in mock-lessons. As a result of analyzing pre-service teachers' knowledge based on PCK factors, most of the pre-service teachers accentuated on understanding boiling point elevation conceptually, whereas some of the others inclined to make students understand boiling point elevation in a scientific way, let the kids use numerical formulas to describe the concept, and motivate them to learn through the examples in real life. The pre-service teachers represented majority of the important facts of boiling point elevation as the knowledge required to understand things conceptually. However, they did not focus on improving the scientific thinking and inquiring levels of the students. Also, the pre-service teachers tended to teach at the level and order of the textbook. In some other cases, they considered the vocabularies and materials in the textbook (which could have been highlighted in the editing sequence) as the main topic to learn, or regarded the goal as giving students the ability to solve exercises in the textbook. It turned out that the pre-service teachers had a low level of knowledge of their students. It is recommended that they should make use of the materials given (such as data related to the misconception of students) during the training session. The knowledge of teaching and evaluating students was described superficially by the pre-service teachers; they merely mentioned the applications of models, such as the cyclic model and discovery learning, rather than thinking of a method related to the goals, or listed general assessment methods.

• Journal of The Korean Association For Science Education
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• v.26 no.7
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• pp.805-812
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• 2006

In this study the description patterns of chemistry textbooks on the boiling point elevation phenomenon and the understanding patterns of high school students, pre-service teachers and chemistry teachers were investigated. High school chemistry II textbooks developed in the 6th and 7th national curricula were analyzed and the conception patterns of subjects on this phenomenon were categorized using a questionnaire developed for this study. The description patterns of science textbooks were classified into three: 'decreasing of surface solvent molecules', 'attraction force between solvent and solute molecules' and 'decreasing of surface solvent molecules and attraction force between solvent and solute molecules'. In the result of the conception analysis, the ratio of 'attraction force between solvent and solute molecules' was high among students, pre-service teachers, and chemistry teachers. There was a propensity that they would like to explain the boiling point elevation in terms of enthalpy rather than entropy, and in order to analyze this propensity, follow-up interviews were carried out.

• Journal of The Korean Association For Science Education
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• v.12 no.1
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• pp.35-46
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• 1992

The purpose of this study was to investigate the most effective teaching model in the study of boiling point elevation. The teaching models were classified into three group-deductive, inductive and analogical teaching models. Learning materials, based on three teaching models respectively, were applied to 11th grade students, and the effect of teaching models were investigated and analyzed. The average achievement score(4.24) of the group treated with the analogical teaching model was higher than those(3.06 respectively) of each group treated with inductive or deductive teaching model(p<0.001). Most students answered that the analogical teaching model was helpful and interesting one for the comprehension of scientific concept.

• Journal of The Korean Association For Science Education
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• v.25 no.2
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• pp.88-97
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• 2005

The purpose of this study was to investigate explanations of science textbooks and science teachers' conceptions related to freezing point depression phenomenon. Seven kinds of middle school science textbooks and five kinds of high school chemistryII textbooks were analyzed for the purpose. The teachers' conceptions were searched by a questionnaire developed in this study. The subjects were 146 science teachers. The explanation types of science textbooks were divided into two; 'Description of the phenomenon' and 'Vapor pressure lowering'. The explanations in most of middle school science textbooks and high school chemistryII textbooks belong to 'Description of the phenomenon' and there was no explanation of the reason. The graphs related to depression of freezing point were diverse, too. Most of the science teachers also did not have scientific conception. The percentage of the teachers who thought that the cause of freezing point depression was blocking of solute in solution was high. But the teacher could not find meaningful relation the 'Blocking of solute' explanation represented for elevation of boiling point with depression of freezing point. It is insisted that entropy concept is need to explain depression of freezing point phenomenon in this study.

• Journal of The Korean Association For Science Education
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• v.22 no.1
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• pp.204-213
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• 2002

In this study, the students' responses on the items of chemistry II in the College Scholastics Ability Test (CSAT) implemented for the past 3 years since 1999 was investigated. The number of applicants and mean score of chemistry II, average percent correct by contents and inquiry process, and the items with high and/or low percent correct are analysed and discussed. The percentage of applicants for natural science track is reduced each year. However, more than 25% of natural science track applied to chemistry II, which ranked second to biology II. The mean score of chemistry II was increased in 2001 along with those of other subjects. There is no difference in average percent correct either by contents or inquiry process. Students performed generally poor at solving test items relating to 'colligative properties of solution' such as 'boiling point elevation' or 'osmotic pressure', and very well at solving test items relating to 'reaction rates'. Educational implications are discussed.