• Title/Summary/Keyword: Chemistry II

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Relationship between the High School Chemistry I, II, and the General Chemistry, and College Students' Cognition about the Subject (대학교 일반화학과 고등학교 화학 I, 화학 II 교과의 연계성 및 일반화학에 대한 대학생들의 인식조사)

  • Moon, Sook-Hee;Lee, Sang-Joa
    • Journal of the Korean Chemical Society
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    • v.55 no.1
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    • pp.112-123
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    • 2011
  • The chemistry has the academic system in which a concept is jointly developed into the single strain, so the contents of the chemistry I II of the high school are very important in the connection of the general chemistry in the university. At this moment, it is possible for high school graduates to be accepted into science or engineering majors without taking the chemistry II. These the highest intensive election subject cause problems of differences in level of understanding and difficult of quality educations. In this study, we have analyzed similarity between the contents of the chemistry I II and the general chemistry. We also analyzed the cognition level of students without taking the chemistry II in understanding the general chemistry level classes. We found that the high school level chemistry I and II introduced about 27% and 62% of the essential concepts required for the general chemistry, respectively. In a case of M university in Chonnam, about 70% of students in the general chemistry classes have no exposure to the chemistry II in their high schools, causing difficulty of understanding new subjects due to their insufficient concepts for classes. The lack of knowledge caused lowering of learning achievement and decrease of interests in chemistry.

Synthesis and Characterization of Schiff Base Metal Complexes and Reactivity Studies with Malemide Epoxy Resin

  • Lakshmi, B.;Shivananda, K.N.;Prakash, Gouda Avaji;Isloor, Arun M.;Mahendra, K.N.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.2
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    • pp.473-482
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    • 2012
  • A novel malemide epoxy containing Co(II), Ni(II) and Cu(II) ions have been synthesized by curing malemide epoxy resin (MIEB-13) and Co(II), Ni(II) and Cu(II) complexes of macrocyclic bis-hydrazone Schiff base. The Schiff base was synthesized by reacting 1,4-dicarbnyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol. The Schiff base and its Co(II), Ni(II) and Cu(II) complexes have been characterized by elemental analyses, spectral (IR, $^1H$ NMR, UV-vis., FAB mass, ESR), thermal and magnetic data. The curing reaction of maleimide epoxy compound with metal complexes was studied as curing agents. The stability of cured samples was studied by thermo-gravimetric analyses and which have excellent chemical (acid/alkali/solvent) and water absorption resistance. Further, the scanning electron microscopy (SEM) and definitional scanning colorimetric (DSC) techniques were confirmed the phase homogeneity of the cured systems.

A Analysis of Teachers' Perception of the Chemistry I & Chemistry II in the 7th National Curriculum and Their Demands on Curriculum Revising (제7차 고등학교 화학 선택 교육과정에 대한 교사들의 인식 및 요구 분석)

  • Hong, Mi-Yeong
    • Journal of the Korean Chemical Society
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    • v.50 no.5
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    • pp.394-403
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    • 2006
  • purpose of this study was to analyze high school chemistry teachers perception of the Chemistry I & Chemistry II in the 7th national curriculum and their demands on the revision of curriculum. A nationwide survey was administered to obtain the responses from 108 high school chemistry teachers. More than half of the participants thought the current curriculum of Chemistry I and Chemistry II needed revising. As the results, a major drawback of Chemistry I was a difficulty in explaining phenomena due to absence of basic concepts, and that of Chemistry II was an excess of the contents for high school science courses. Unfortunately, it was found out that inquiry activities existed only in name, especially in case of Chemistry II. Regarding the manner of content organization of Chemistry I in new curriculum, demand on a concept-based approach outnumbered theme-based approach. For revising Chemistry, the majority of participants demanded basic chemistry concepts to be introduced, without supplementation of quantitative approaches and deepening level of concepts. An urgent request for Chemistry II was reducing content by shifting relevant concepts to Chemistry I. Implications for high school chemistry education including revising curriculum were discussed.

Surface Complexation Modeling of Ni(II), Co(II), and Sr(II) Adsorption on Amorphous Alumina (무정형 알루미나에서의 Ni(II), Co(II), Sr(II) 흡착의 표면착물 모델링)

  • Park, Yeong Jae;Park, Kyoung Kyun;Suh, Moo Yul;Yoon, Soo Kyoung;Choi, Kwang Soon;Jee, Kwang Yong;Kim, Won Ho
    • Journal of the Korean Chemical Society
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    • v.44 no.4
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    • pp.305-310
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    • 2000
  • Adsorpdon behaviors ofNi(II), Co(II), Sr(II), and(I) ions were nvestigated on amorphous alumina with varying pH at three different etalion concentrations under the condition of 0.I M ionlc strength.With increasingmctalion concentration, the percentage of adsorption decreased and the adsorption edge was shifted to a higher pH value. The adsorption data obtained usingthe metal ion concentration of $1.0{\times}10^{-4}$M were quantitatively analyzed by surfacecomplexation modelingof Ni(II) and Co(II) ions adsorbed at high pH (>8)were found to be in hydrolyzed forms.

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Ag(Ⅰ) Ion Selective Macrocyclic Ligands: The Complexation and Liquid Membrane Transport Phenomena of Benzylated Nitrogen-Oxygen Donor Macrocyclic Ligands (Ag(Ⅰ) 이온 선택성을 갖는 거대고리 리간드: 벤질 치환기를 갖는 질소-산소 주개 거대고리 리간드의 착물 형성과 액체막 이동 현상)

  • Kim, Jeong;Ahn, Tae Ho;Lee, Myoung Ro;Cho, Moon Hwan;Kim, Si Joong
    • Journal of the Korean Chemical Society
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    • v.43 no.2
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    • pp.167-171
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    • 1999
  • An investigation of the interaction of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pb(II) and Ag(I) with two N,N'-dibenzylated nitrogen-oxygen mixed donor macrocyclic ligands, has been carried out. Tle log K values for the respective complexes in 95% methanol have been determined potentiometrically. Both ligands have formed stable complex with only Cu(II) and Ag(I) ion. Transport measurements in a bulk liquid membrane system exhibited a very high selectivity of Ag(I) ion over the other metal ions used.

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Synthesis of Co(II), Ni(II) and Cu(II) Complexes from Schiff base Ligand and Reactivity Studies with Thermosetting Epoxy Resin

  • Lakshmi, B.;Shivananda, K.N.;Prakash, Gouda Avaji;Rama, Krishna Reddy K.;Mahendra, K.N.
    • Bulletin of the Korean Chemical Society
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    • v.32 no.5
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    • pp.1613-1619
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    • 2011
  • A hybrid thermosetting maleimido epoxy compound 4-(N-maleimidophenyl) glycidylether (N-MPGE) containing Co(II), Ni(II) and Cu(II) ions was prepared by curing N-MPGE and tetradentate Schiff base Co(II), Ni(II) and Cu(II) complexes. The curing polymerization reaction of N-MPGE with metal complexes as curing agents was studied. The cured samples were studied for thermal stability, chemical (acid/alkali/solvent) and water absorption resistance and homogeneity of the cured systems. The tetradentate Schiff base, 3-[(Z)-2-piperazin-1-yl-ethylimino]-1,3-dihydro indol-2-one was synthesized by the condensation of Isatin (Indole-2, 3-dione) with 1-(2-aminoethyl)piperazine (AEP). Its complexes with Co(II), Ni(II) and Cu(II) have been synthesized and characterized by microanalysis, conductivity, Uv-Visible, FT-IR, TGA and magnetic susceptibility measurements. The spectral data revealed that the ligand acts as a neutral tetradentate Schiff base and coordinating through the azomethine nitrogen, two piperazine nitrogen atoms and carbonyl oxygen.

Adsorption Characteristics of Pb(II) and Cr(III) onto C-Methylcalix[4]resorcinarene (C-Metylcalix[4]resorcinarene에서 Pb(II)와 Cr(III)의 흡착 특징)

  • Jumina, Jumina;Sarjono, Ratnaningsih Eko;Siswanta, Dwi;Santosa, Sri Juari;Ohto, Keisuke
    • Journal of the Korean Chemical Society
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    • v.55 no.3
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    • pp.454-462
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    • 2011
  • A study on the adsorption characteristics of Pb(II) and Cr(III) cations onto C-methylcalix[4]resorcinarene (CMCR) has been conducted. CMCR was produced by one step synthesis from resorcinol, acetaldehyde, and HCl. Most parameters in batch system confirm that CMCR is a good adsorbent for Pb(II) and Cr(III). Cr(III) uptake was bigger than that of Pb(II), but Cr(III) adsorption rate was slower than Pb(II). The adsorption kinetic of Pb(II) and Cr(III) adsorptions in batch followed pseudo $2^{nd}$ order kinetics model, but the kinetic of Pb(II) adsorption in fixed bed column system followed first order model. Desorption studies to recover the adsorbed Pb(II) was performed sequentially with distilled water and HCl, and the results showed that the adsorption was dominated by chemisorption.