• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.479-486
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• 2010

The purposes of this study are to investigate the description of scientifically debatable carbonic acid in the Korean high school textbooks, characterize the physical properties of 'carbonic acid solutions' by using an MBL set-up and compare the properties with textual ones. Four different aqueous solutions of carbon dioxide have been prepared and analyzed: naturally aerated aqueous solution, dry ice-dissolving solution, $CO_2$-bubbling solution and commercial carbonic acid water. Experimental findings showed that pH and conductivity of these 4 solutions ranged from 3.85 to 5.66 and from 0.21 ${\mu}S$/cm to 272.1 ${\mu}S$/cm, respectively. Out of these solutions, the dissociation constant($K_{a1}$) of the bubbling solution at room temperature could be calculated to $5.7{\times}10^{-7}$ which value is comparable to the textual $4.3{\times}10^{-7}$ within experimental errors, which means that textual compound is not pure carbonic acid but the equilibrated mixture of carbonic acid and the aqueous solution of carbon dioxide. On the other hand, textual analysis showed that most of high school textbooks used carbonic acid as an example of weak acid and buffer solution of the blood but none of them distinguished the carbonic acid from the aqueous solution of carbon dioxide. Only one textbook, however, tiered two species in the chemical equation.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.363-377
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• 2002

The purpose of this study was to improve the problems of the voltaic cell described in the science textbooks of secondary schools. For this purpose, the contents of science textbooks which are related to the voltaic cell were analyzed and the problems which were not explained clearly by theorems were tried to be explained by experiments, and lastly sug-gestions were made toward the improvements regarding the voltaic cell in the science textbooks. The findings are that there are problems on the ways of ensuring whether the voltaic cell operates properly as a chemical battery, on the explanation of why the hydrogen bubbles form at the zinc electrode, on the cell potential, on the unification of the electrode terminology used, and on the mention of the current. Solutions to the problems except the cell potential were suggested. According to the experiment, the theoretical potential was calculated by considering the potentials of redox reactions at the two electrodes of the cell and by taking into account the characteristics of the electrodes such as the work function, ionization energy, stan-dard reduction potential, and electronegativity.The cell potential of the voltaic cell is explained by several factors. In the improved version of the textbook's introduction section to the voltaic cell, it is necessary to describe the voltaic cell his-torically.For the conceptual section, it should be explained in terms of the Daniel cell.

• Journal of the Korean Chemical Society
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• v.62 no.3
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• pp.214-225
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• 2018

In this study, we tried to find out how heat and thermal energy terms are defined and used in Korean science textbooks, and to see if there are any differences in the meaning of these terms used in different areas of science. For this purpose, the contents of 52 science textbooks of elementary, middle and high school published by the 2009 revised curriculum were analyzed. The definition of the term heat is given in the middle school Science(1) and the high school Physics I and II textbooks. Most textbooks define heat as "energy transferred due to a temperature difference (Type I)". Only one textbook of Physics I defines heat as "transfer of energy due to a temperature difference (Type II)". The definition of thermal energy is mostly presented in the middle school Science (2) and the high school Physics I textbooks. Physics I textbooks define the thermal energy as "molecular kinetic energy (Type III)", while Science(2) textbooks define it as Type I or "energy causes temperature change or phase transition of matter (Type IV)". In the texts of textbooks, heat is mainly used as the meaning of Type I or Type III. Thermal energy is mainly used as Type III, but it is also used as Type I in the high school Physics and Chemistry textbooks. The meanings of heat and thermal energy terms used are differed by the area of science. They are mainly used as type I or type III in Physics and Chemistry textbooks, and used as type III in Life Science and Earth Science textbooks.

• Journal of the Korean Chemical Society
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• v.50 no.2
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• pp.141-152
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• 2006

In this study computer assisted instruction materials for the ‘Solution' chapter in high school chemistry II textbook were developed based on a view of particle and analyze the effect of the materials on 10th and 11th high school students. The contents of developed materials are dissolution, vapor pressure, the change of boiling point and freezing point, osmosis, and so on which are the major contents of Solution chapter in high school chemistry II textbook. Materials were developed with using animation and simulation for students understanding of the phenomena with a particle view point. Many phenomena in a solution were not simplified by colligative property of solution, but tried to explain by the concept of attraction between solute and solvent molecules. This computer assisted learning materials were developed using Flash 5.0 and Flash 6.0 Action Script. Educational effects of the materials on 10th and 11th grade students represented statistically meaningful increase of concept understanding. Especially the materials were effective to the transition stage or formal stage students in 10th grade and formal stage or the natural science major students in 11th grade.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.563-571
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• 2019

The purpose of this study is to analyze the safety contents presented in high school science textbooks of the 2015 revised national science curriculum. For these, we found safety contents in the inquiries and appendices of 63 science textbooks: integrated science, science inquiry experiment, physics I, II, chemistry I, II, biology I, II, and earth science I, II. We analyzed these safety contents using six safety factors based on the seven standards for safety education. The main results are as follows: First, 81(46.0%) inquiries among 176 curriculum inquiries contain safety contents, and these contents are mainly found in chemistry textbooks, and the least in 'science inquiry experiment' textbooks. Second, safety contents are found the most in 'laboratory safety rule', followed by 'safety symbol' and 'usage of protection equipment'. Third, the safety contents of appendices are mainly in 'laboratory safety rule' and 'accident treatment'. Based on these results of this study, it is concluded that these textbooks have problems; that there is a big difference in describing safety contents in each textbook; that these safety contents are not presented in detail and that the educational effect is reduced. Furthermore, the safety symbol is not standardized. We also discussed ways to improve the safety contents of science textbooks.

• Journal of the Korean Chemical Society
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• v.65 no.5
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• pp.382-396
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• 2021

This study analyzed illustrations presented in middle school science 14 paper textbooks and 14 digital textbooks under the 2015 revised curriculum in terms of gender stereotypes. In both paper and digital textbooks, the most common type of illustration was multiple pupils. For pupils, the frequency of gender was balanced in both paper and digital textbooks. However, there were differences among publishers in digital textbooks. In both paper and digital textbooks, girls showed a higher frequency than boys in learning activities. However, the opposite tendency was observed in non-learning activities. In particular, non-learning activities of digital textbooks showed gender imbalance among all publishers. In both paper and digital textbooks, behavioral characteristics were mostly described to be active without gender differences. But, there were differences among publishers in digital textbooks. For adults, men showed a higher frequency than women in both paper and digital textbooks. Gender frequency was balanced in family activities, however, men showed a higher frequency in social activities. Unlike paper textbooks, digital textbooks were gender balanced in occupational activities. In both paper and digital textbooks, the number of occupations in which men appeared more frequently was higher than that in which women appeared more frequently. Especially, men showed a higher frequency than women in both scientist and researcher. Behavioral characteristics were mostly biased in terms of gender in both paper and digital textbooks.

• Journal of the Korean Chemical Society
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• v.52 no.3
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• pp.303-314
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• 2008

The purpose of this study was to understand the experiment for measuring chemical reaction rate by precipitate formation and to develop experiments applying small-scale chemistry. For this study, the experimental method for measuring the effect of concentration and temperature on chemical reaction rates presented in the 10 high school science textbooks were classified by their experimental methods of confirming production. Subsequently, problems observed in carrying out the experiments for measuring chemical reaction rates by precipitate formation frequently presented in the 10 high school science textbooks were analyzed. Experiments applying small-scale chemistry were developed measuring chemical reaction rate by precipitate formation. According to the result of this study, there were some problems in the experimental method of precipitate formation for measuring chemical reaction rates presented in the high school science textbooks. Those problems in the science textbook experiments were insufficient specification of mixing methods of reaction solutions, obscurity of knowing when the character letter X disappeared, time delay in collecting the experimental data, formation of hazardous sulfur dioxide, uneasiness of fixing water bath container, controlling the reaction temperature, and low reproducibility. Those problems were solved by developing experiments applying smallscale chemistry. Presenting the procedure of mixing reaction solutions on the A4 reaction paper sheet made the experimental procedure clearly, using well plates and stem pipette shortened the reaction time and made it possible to continuously collect the experimental data. Furthermore, the quantity of hazardous sulfur dioxide was reduced 1/7 times and the time when the character letter X disappeared could be observed clearly. Since experiments for measuring the effect of concentration and temperature on chemical reaction rates could be performed in 30 minutes, the developing experiments applying SSC would help students understand the scientific concepts on the effect of concentration and temperature on chemical reaction rates with enough time for experimental data analysis and discussion.

• Journal of the Korean Chemical Society
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• v.48 no.6
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• pp.645-653
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• 2004

The purpose of this study was to compare and analyze the cognitive levels of 11th grade students and those required in high school chemistry I textbooks standardized by the 7th national education curriculum. For this study, the cognitive development stages of 456 11th grade students were surveyed using short-version GALT (group assessment of logical thinking). Furthermore, 15 basic concepts were extracted from the contents on water and air, 2 units in chemistry I order to analyze the cognitive levels necessary for understanding high school textbooks, using CAT (curriculum analysis taxonomy). The results showed that 52.5% of the surveyed 11th grade students reached the formal operational level, 28.3% transitional levels, and 19.5% concrete operational levels. 68.9% of the academic high school students and 6.6% of the technical high school students reached the formal operational levels, and the ratio of formation was very different in each logics. As a result of the analyzing the cognitive levels needed for understanding chemistry I textbook contents, in spite of a change in national education curriculum, there were no great change in cognitive levels required by scientific concept except some inquiry activities. The cognitive levels in high school chemistry I textbooks by the 7th national education curriculum appeared higher than the cognitive levels of 11th grade student, but cognitive levels of inquiry activities were similar to the cognitive levels of the students. Chemistry teachers thought of chemistry I textbooks by the 7th national education curriculum as desirable because scientific concepts were reduced and a lot of real life materials were adapted. However, they pointed out a problem of difference in contents levels compared with chemistry I textbooks because scientific concepts were greatly reduced in chemistry I textbooks. The cognitive levels required in chemistry I textbooks still appeared higher than those of the students. Consequently, various teaching and learning methods and materials will have to be developed to be suitable for the students' cognitive levels.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.73-83
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• 2008

The purpose of this study was to investigate the types of conceptions of mixing phenomena related to dissolution and diffusion in high school students. The subjects of the investigation consisted of 108 students who took chemistry I course at 11th grade and 29 students who took chemistry II course at 12th grade. For this study, it was found that the many students had the alternative conception that chalk didn't dissolve in water because chalk was a nonpolar material. Most of the students understood the phenomena which carbon tetrachloride and water will not mix as the attraction conception. But many of the other students understood the phenomenon as characteristic of the materials such as difference of density. Many of the students understood the phenomenon of mixing ethanol and water constantly as ‘Attraction conception'. The phenomenon which is mixed ink and water was just accepted by the most students as the spreading of ink in water without understanding the reason of mixing. The phenomena of mixing iodine and carbon tetrachloride was understood as ‘Space conception' or ‘Attraction conception'. It could be inferred that the diverse alternative conceptions related to dissolution and diffusion phenomena were generated by the absence of entropy concept. Therefore, the explanations of science textbooks related to dissolution and diffusion phenomena need to change for students to understand them correctly.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.633-644
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• 2003

The purpose of this study was to analyze the inquiry elements and inquiry activity of the inquiry area in chemistry I textbooks authorized by 7th curriculum. It was to confirm suitable reflection of the 7th science curriculum and to find educational suggestions of inquiry learning. It was found that the basic inquiry elements except measuring and classifying were well reflected on the textbooks. However, only several integrated inquiry elements and the inquiry activities were well reflected on the same textbooks. For the integrated inquiry elements, interpreting data was shown as the tower above the rest inquiry elements. In the analysis of inquiry activity, the numbers of experiment is placed almost half of all inquiry activities. The sum of two numbers of investigation and discussion is similar ratio to experiment but field trip and project are rarely or low ratio. As the integrated inquiry elements and inquiry activities were not balanced for various inquiry learning. It is suggested that learners be educated with complementary of these aspects in inquiry learning.