• Journal of the Korean Chemical Society
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• v.52 no.5
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• pp.550-560
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• 2008

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.175-188
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• 2009

In this study, we developed an experimental method of the Charles' law applicable to school. Science textbooks and literatures on this principle were analyzed to extract factors utilized in organizing the experimental setup and method. A combined structure such as with a vial and a glass tube, the former of which is for deciding the total volume and the latter of which is for easy measurement of volume, was better in measurement of volume with temperature rather than a simple structure such as syringe. Use of graduated cylinder as a water bath to control the temperature showed advantage in cooling time than using other bath of larger volume such as a beaker. A liquid drop was used as a plug in the glass tube. This plug has little resistance with the glass wall when the gas volume changes. Water as a liquid drop in the glass tube had a significant effect in volume change of gas due to evaporation, especially in the beginning of the measurement. Glycerol showing negligible effect in volume change was used. This method took about one hour and produced a good linear relationship between the temperature and volume of gas with $R^2$ = 0.999 and absolute zero temperature = $-216.7\;{^{\circ}C}$. The Charles' law experiment developed in this study can be performed with appropriate adjustment of procedure considering the purpose of the curriculum of science and chemistry subject at each school level.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.1042-1055
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• 2011

The purpose of this study was to compare the conceptual and algorithmic problem solving ability on Boyle's law and Charles's law according to cognitive levels and characteristics of students in middle school 1st grade students. For this study, questionnaire items of conceptual and algorithmic problem solving ability were developed. and the problem solving ability according to cognitive levels and characteristics of students was compared. The long-term memory effect in conceptual and algorithmic problem solving ability according to cognitive levels was investigated, and problem solving process were analyzed by questionnaire items. In the results of this study, conceptual problem solving ability was higher than algorithmic problem solving ability in all cognitive levels. There was statistically significant difference in concrete operational period and transitional period students. In comparison of the long-term memory effect in conceptual and algorithmic problem solving ability, formal operational period students had the long-term memory effect. There was no statistically significant difference in the conceptual and algorithmic problem solving ability according to private education among the characteristics of students. But there was statistically significant difference in the problem solving ability according to experiences of the scientific activities and hopes to related scientific careers. From results of analysis of problem solving process, it is known that the students had a tendency to just remember macroscopic phenomena and to solve the problems without understanding the concepts. Therefore, teaching and learning strategy is necessary to replace unscientific concepts by the scientific concepts through identifying students's unscientific concepts in advance.

• Journal of The Korean Association For Science Education
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• v.34 no.2
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• pp.79-92
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• 2014

The purpose of this study is to develop an inquiry-based argumentation task for use in science teachers' professional development by providing them with the substantial experience of argumentation. To do so, the study has developed an argumentation task by utilizing the experiment on the Charles' Law of gas and revised by applying to eight teachers three times. We have revised the questions by analyzing three issues that have been revealed throughout this process in ways that facilitated teachers' argumentation. The effects of revision have been confirmed by the improvements in teachers' argumentation pattern. Three issues have been identified in developing argumentation tasks for science teachers' professional development and they are as follows: determining the openness of the structure of a question, achieving cognitive conflict and convergence of opinions at the same time, and ways of utilizing various evidence. As the task has been revised in ways that enabled scientific approach to the inquiry topic and facilitated the convergence of various opinions, the participants' argumentation patterns have improved both quantitatively and qualitatively. Meanwhile, the inclusion of an actual experiment has not influence their argumentation, while the observation of experimental data has been used as the core evidence according to the character of the problem. Based on the study's result, we suggest practical implications for developing argumentation tasks for science teachers in more varying contexts.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.107-113
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• 2008

We investigated the electro-optical characteristics of an ICP(Inductively Coupled Plasma) light source depending on driving temperature, and length of discharge tube. An electro-optical stability of a sample at operating was measured to see a steady state of a sample. In this results, we can see that a stability of power loss and luminous flux of a sample at operating of upper 70[min] was 1.45[%1 and 0.36[%]. We measured the optical characteristics of a sample in a thermal chamber operated at a specific temperature divided into 5 steps. While luminance increased with temperature increasing, the decrement of luminance a eared at u or $46.7[^{\circ}C]$. According to Parchen's and Boyle-Charles' law, we can speculate that a pressure was increased and a higher voltage was needed but a ballaster having a rating power can't support a higher voltage corresponding to a pressure change, 0.02[Torr] at $46.7[^{\circ}C]$. Moreover, we measured an a lied power and current of samples depending to a various length of a discharge tube.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.611-620
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• 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 Association For Science Education
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• v.26 no.4
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• pp.510-517
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• 2006

This study investigated the influences of situational interest, attention, and cognitive effort on drawing as a method to assist students to connect and integrate multiple external representations provided in learning chemical concepts. Seventh graders (N=178) at two coed middle schools were taught about the "Boyle's Law" and the "Charles's Law" for two class hours through drawing. They observed macroscopic phenomena through demonstrations. After these observations, they drew their mental model from the external verbal representation, and then compared their drawings with external visual representation. The tests assessing situational interest, attention, cognitive effort, and conceptual understanding were administered as post-tests. Correlation and path analyses supported a causal model which situational interest had a positive direct effect on attention to the drawing. Attention led to conceptual understanding directly as well as through cognitive effort. These results suggest that situational interest may be induced by drawing first of all, and attention and cognitive effort may be direct causes of conceptual understanding in drawing. Educational implications are discussed.

• Journal of The Korean Association For Science Education
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• v.28 no.6
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• pp.675-684
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• 2008

This study investigated the effects of the prescribed instructional strategy for reducing students' connecting errors in learning chemistry concepts with multiple external representations by students' field independence-dependence. Seventh graders (N=126) at a coed middle school were assigned to control and treatment groups. The students learned "Boyle's Law" and "Charles's Law" for two class periods. Results revealed that the students in the treatment group scored significantly higher than those in the control group in a conception test. The scores of the treatment group were significantly higher than those of the control group in a motivational learning test, especially in 'attention' of the test. However, there was no significant interaction between the instruction and students' field independence-dependence in the two tests. Most students in the treatment group perceived the instruction positively in cognitive and motivational aspects.

• Journal of The Korean Association For Science Education
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• v.28 no.5
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• pp.471-481
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• 2008

This study investigated connecting errors by students' field independence-dependence in learning chemistry concepts with multiple external representations in current science textbooks. Seventh graders (N=196) at a middle school were assigned to the BL and CL groups, which were respectively taught "Boyle's Law" and "Charles's Law." A field independence-dependence test was administered. After learning the target concept with text and picture emphasizing the particulate nature of matter, a connecting test was also administered. Five types of connecting errors were identified: Insufficient connection, misconnection, rash connection, impossible connection, and failing to connect. 'Failing to connect,' 'Misconnection,' and 'Rash connection' were found to be the frequent types of connecting errors regardless of the target concepts. The frequencies and percentages of the types of connecting errors were not significantly different between the field independent and field dependent students. Educational implications of these findings are discussed.

• Journal of the Korean Chemical Society
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• v.50 no.6
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• pp.477-485
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• 2006

study investigated the influences of the forms of verbal external representations and students' verbal learning style in learning chemical concepts with drawing as a method to assist students in connecting and integrating multiple external representations. Seventh graders (N=133) at a coed middle school were assigned to formal drawing (FD) and personalized drawing (PD) groups. Students in the PD group were provided words at personalized style as verbal external representations for drawing, while those in the FD group were provided words at formal style. All students were taught about Boyles Law and Charless Law for two class hours. Results revealed that the scores of a conception test for the PD group were significantly higher than those for the FD group. In a situational interest test, students with strong verbal learning style preference scored significantly higher than students with weak verbal learning style preference in the two groups. Most PD group students were found to prefer to read verbal external representations at personalized style for drawing rather than at formal style, and perceived their activities positively upon cognitive, affective and motivational aspects. Students with strong verbal learning style preference had more positive perceptions about their activities than students with weak verbal learning style preference especially upon affective and motivational aspects.