This project explored the strategies that undergraduate and graduate chemistry students engaged in when solving classification tasks involving microscopic (particulate) representations of chemical substances and microscopic and symbolic representations of different chemical reactions. We were specifically interested in characterizing the basic features to which students pay attention while classifying, identifying the patterns of reasoning that they follow, and comparing the performance of students with different levels of preparation in the discipline. In general, our results suggest that advanced levels of expertise in chemical classification do not necessarily evolve in a linear and continuous way with academic training. Novice students had a tendency to reduce the cognitive demand of the task and rely on common-sense reasoning; they had difficulties differentiating concepts (conceptual undifferentiation) and based their classification decisions on only one variable (reduction). These ways of thinking lead them to consider extraneous features, pay more attention to explicit or surface features than implicit features and to overlook important and relevant features. However, unfamiliar levels of representations (microscopic level) seemed to trigger deeper and more meaningful thinking processes. On the other hand, expert students classified entities using a specific set of rules that they applied throughout the classification tasks. They considered a larger variety of implicit features and the unfamiliarity with the microscopic level of representation did not affect their reasoning processes. Consequently, novices created numerous small groups, few of them being chemically meaningful, while experts created few but large chemically meaningful groups. Novices also had difficulties correctly classifying entities in chemically meaningful groups. Finally, expert chemists in our study used classification schemes that are not necessarily traditionally taught in classroom chemistry (e.g. the structure of substances is more relevant to them than their composition when classifying substances as compounds or elements). This result suggests that practice in the field may develop different types of knowledge framework than those usually presented in chemistry textbooks.

This research proposed to evaluate whether homework or daily quizzes were better for academic success within high-school pre-AP chemistry or if differences in the two methods were detectable. The study involved two years of data where homework was assigned and graded and one year of data where homework was suggested but daily quizzes provided the assessment. The mean of each of the unit tests were evaluated and t-tests were calculated. The results showed that over two-thirds of the units had statistically significant data when daily quizzes were utilized.

Active participation in the learning process enhance students’ critical thinking and problem-solving skills. We implemented peerocused, active learning, recitation sessions with the large-enrollment sections for General Chemistry I courses at Mississippi State University (MSState) over a period of four semesters beginning in Spring 2016. The peerocused recitation program was a success improving student final (standardized ACS) exam scores, pass/fail rates for the course, and continuation on to General Chemistry II (CH 1223) courses. Peerocused collaborative learning and students possessing ownership over their learning significantly enhanced academic outcomes of our program. Worked-example effect is the best known and apparently the most effective cognitive load reducing technique. We incorporated a modified version of worked examples, employing “incorrect worked examples” and studied the impact of incorrect worked examples vs correct worked examples. We hypothesized that looking for errors in incorrect worked examples would achieve greater attention and would prompt students to actively engage on calculation steps than correct worked examples. Eye-tracking results showed that incorrect worked example format was effective at obtaining student attention and engaging students actively on calculation steps. Survey results showed that incorrect worked example format inspired students’ motivation and enhanced student engagement and attentiveness to examine the worked examples intensively. This research provided insights on student focus while reading and learning chemistry worked examples, and opened new avenues for supporting online learning and usage of tablet PC in the learning process. Laboratory experiments provide students the opportunity to obtain hands-on experience on laboratory techniques and instrumentation. We created a biochemistry laboratory course (CH4990) for third-year chemistry major undergraduate students at Mississippi State University. I wrote the biochemistry lab manual consisting of eleven experiments, which involved protein and DNA extraction, ion-exchange chromatography, UV/vis spectroscopy, SDS PAGE electrophoresis, and enzyme kinetics experiments. A new laboratory experiment was incorporated which allowed students exposure to peptide sequencing and proteomics experiments in conjunction with mass spectrometry. The CH4990 biochemistry lab course is open for enrollment in Fall semesters since Fall 2018.

Submitted by Matheus Almeida Bauer Zytkuewisz (matheus.bauer@unesp.br) on 2019-01-29T13:12:00Z No. of bitstreams: 1 Dissertação_Matheus_Almeida_Bauer_Zytkuewisz.pdf: 5568207 bytes, checksum: c6747256bad7b516b287fd10aa92c0ed (MD5) / Approved for entry into archive by Ana Carolina Gonçalves Bet null (abet@iq.unesp.br) on 2019-01-31T12:11:11Z (GMT) No. of bitstreams: 1 zytkuewisz_mab_me_araiq_int.pdf: 5431251 bytes, checksum: 6c4f196e54624f6719164e31587bd433 (MD5) / Made available in DSpace on 2019-01-31T12:11:11Z (GMT). No. of bitstreams: 1 zytkuewisz_mab_me_araiq_int.pdf: 5431251 bytes, checksum: 6c4f196e54624f6719164e31587bd433 (MD5) Previous issue date: 2018-12-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho de mestrado teve como temática geral a experimentação no ensino de Química, especificamente o emprego da perspectiva investigativa de ensino no nível superior. A pesquisa visou verificar como a inserção de um erro proposital em uma atividade experimental possivelmente suscitaria no amadurecimento e formação do Espírito Científico dos alunos do curso da licenciatura. A metodologia de pesquisa teve abordagem qualitativa do tipo Estudo de Caso, e as fontes de informação foram compostas de sujeitos e documentos. Os sujeitos foram os alunos do curso de licenciatura cursando no ano de 2017 na disciplina de Laboratório de Ensino de Química Geral, e os documentos textuais foram um roteiro alterado, um formulário de proposição de hipóteses adido de um roteiro provisório, e um relatório final, no qual os alunos também propuseram um roteiro retificado para a realização da atividade experimental. Ainda, foi realizado um grupo focal com os participantes da atividade, e os alunos também responderam a um questionário, o qual providenciou suporte para a conseguinte entrevista individual. O tratamento e análise das informações coletadas se deu pela Análise de Conteúdo, para a qual foram utilizadas categorias a priori para o questionário e entrevista reflexiva, e categorias a posteriori para o grupo focal e documentos textuais. Como conclusão do estudo, concebe-se que a intervenção aqui proposta, a qual é dotada de um elemento inédito, por si só, em ação pontual, não foi capaz de suscitar a níveis significativos características do espírito científico nos sujeitos. Porém, a mesma se revelou como excelente pedra angular para o início da construção do espírito científico e de noções mais adequadas de ciência nos sujeitos. / The work herein presented had as general theme practical work regarding chemical education, and had its scope on the employment of inquiry-based activities at the undergraduate level. This research intended to unveil how the interposition of a purposeful error on a experimental activity could promote the formation and maturation of the scientific spirit on undergraduate students. The research methodology had used a qualitative approach, on the manners of a case study, and the information sources regarded subjects and documents. The subjects were the students undergoing the “Laboratório de Ensino de Química Geral” course, and the textual documents were a modified script, a hypothesis form coupled with a provisional script and a final report, in whose the students should add a rectified script that would allow them to perform the activity without issues. In addition, the students composed a focus group with the groups that participated in our intervention, as well as an individual questionnaire regarding aspects of nature of science. The latter provided support for the accomplishment of individual interviews with the students. The data gathering and treatment of collected data was done in the ways of the content analysis, for whose we employed a priori analytical categories for the questionnaire and individual interview, and established a posteriori categories for the focus group and textual documents. As a conclusion, we conceived that the intervention proposed on this work, which features a brand-new tool for inquiry, by itself was unable to achieve significant aspects of the scientific spirit on the subjects. However, the intervention unraveled excellent potentialities as cornerstone for the scientific spirit and more informed notions of science on the subjects. / 001

The prevalent trend in chemistry instruction relies on what has been described as the classroom game. In this model, students take a passive role and the instructor does all the explaining (thinking), and learning is trivialized to knowing the correct answers (memorizing) and being able to produce them when prompted (regurgitating). The generation of explanations is central to scientific and technological development. In the process of figuring out explanations, the generation of inferences relies on the application of skills associated with scientific behaviors (e.g., analytical reasoning and critical thinking). The process of explanation generation causes a deeper analysis and revision of the scientific models, thus impacting the conceptual understanding of such models. Although the process of generating authentic explanations is closer to the experience of doing science, this process is seldom replicated in science instruction. Self-explaining refers to the generation of inferences about causal connections between objects and events. In science, this may be summarized as making sense of how and why actual or hypothetical phenomena take place. Research findings in educational psychology show that implementing activities that elicit self-explaining improves learning in general and specifically enhances authentic learning in the sciences. Research also suggests that self-explaining influences many aspects of cognition, including acquisition of problem-solving skills and conceptual understanding. Although the evidence that links self-explaining and learning is substantial, most of the research has been conducted in experimental settings. The purpose of this work was to advance knowledge in this area by investigating the effect of different self-explaining tasks on self-explaining behavior and the effect of engaging in different levels of self-explaining on learning chemistry concepts. Unlike most of the research in the field, this work did not focus on advancing procedural knowledge through self-explanation of examples or conceptual understanding through self-explanation of textual information and concepts. Instead, it focused on an experience closer to doing science by presenting a familiar phenomenon to the participants and a fact that would potentially induce cognitive imbalance to then prompt them to self-explain. This work used a multi-condition, mixed-method approach to categorize students' self-explaining behaviors in response to learning tasks and link it to the performance in a post-learning task. Students were randomly assigned to conditions that included the following: studying an experts' explanation, explaining correct and incorrect answers, explaining agreement with another's answer, and explaining one's own answer for others to use. Data were gathered in the classroom ecology of a university, large-enrollment general chemistry course. Content and construct validity evidence support the functionality of the research instruments for the assessment of conceptual understanding of entropy and the Second Law of Thermodynamics. An in-depth analysis of the post-learning task showed that the data collected from the instrument is reliable, consistent and reproducible. Findings supported an association between the self-explaining tasks and students' self-explaining behaviors. Results showed distinct categorical self-explaining behaviors in students' written responses. These self-explaining behaviors were associated with the self-explaining task given to the students. Thoughtful design of learning tasks can effectively elicit engagement in sophisticated self-explaining in natural, large-enrollment college chemistry classroom environments. Comparison analyses of performance in the post-learning task suggested that in the context of large-enrollment college chemistry classroom environments, self-explaining activities improved students' conceptual understanding in chemistry. Overall, the work showed that students can self-explain chemical phenomena and apply the underlying chemistry concepts in the resolution of novel problems without direct intervention of an instructor. This work supports the incorporation of self-explaining activities in the repertoire of teaching practices of both experienced and novice instructors for general chemistry courses.

There is considerable qualitative and quantitative data to suggest that chemistry in Australia is in a state of decline. This trend has been in evidence for the last fifteen years and is most evident from a progressive decline in demand for tertiary chemistry courses over this period despite an overall increase in demand for science courses in Australian universities. There is quantitative evidence to suggest that Australia is experiencing a ‘skills shortage’ of ‘trained chemists’ to support the development and sustainability of the chemical industry and, perhaps more significantly, the proportion of chemistry graduates entering the teaching profession is also decreasing. / This thesis examines the reasons for this decline in the status of Australian chemistry by conducting a series of interviews with Heads of Departments of Chemistry in Australian universities to find out their concerns on this issue and, more specifically, to ascertain the actions that they are enacting to address the decline in demand for tertiary chemistry courses and the difficulty in retaining students in the chemistry major. This process also revealed numerous constraints, most significantly, financial constraints, that impede ‘change’ in the tertiary chemistry sector. (For complete abstract open document)

Orientador: Pedro Faria dos Santos Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-11T11:58:23Z (GMT). No. of bitstreams: 1 Reis_AdrianodeSouza_M.pdf: 1594474 bytes, checksum: 4085fd3be588cce4f866d8ebc2f1c832 (MD5) Previous issue date: 2008 / Resumo: O enfoque deste trabalho é o ensino de química, abordando situações cotidianas de pessoas comuns, visando a interpretação destas situações do ponto de vista químico. O principal objetivo é a elaboração de um material que seja útil para graduandos e professores, particularmente os professores de química que atuam no nível médio e superior. As ligações hidrogênio e suas propriedades compõem a maior parte da discussão deste texto. Vários contextos são utilizados, tais como, química ácido-base, capilaridade, formação do DNA e mutações genéticas, água líquida e sua contribuição em diversos fenômenos, química da sensação dos sabores doce e amargo, além de outras situações corriqueiras. As situações abordadas não são utilizadas como objetos de estudo, mas como forma de discutir alguns aspectos, propriedades e características das ligações hidrogênio. Além disso, o texto discute a melhor forma de entender ligação hidrogênio em diferentes níveis. A seqüência do texto coloca, gradualmente, as principais propriedades das ligações hidrogênio em diferentes contextos. Inicialmente o modelo puramente eletrostático é utilizado para explicar algumas situações interessantes. Em seguida, o modelo puramente eletrostático tradicional é questionado e observa-se que ele não é conveniente para explicar todos os fenômenos, sendo então questionado e repensado ao longo do texto. Novos argumentos são usados para explicar a ligação hidrogênio, agora usando o conceito de modelo eletrostático com uma componente covalente. Esta contribuição torna o modelo mais complexo que o anterior e inclui outras idéias além dos ¿pontinhos¿ (X ¿ H ....... X), normalmente usados para representar a contribuição puramente eletrostática desta interação. Muitas propriedades das ligações hidrogênio são apresentadas e discutidas ao longo do texto, utilizando este novo conceito / Abstract: The focus of this work is chemistry teaching, approaching common people's daily situations, and seeking the interpretation of these situations in a chemical point of view. The main goal is the elaboration of an useful didactic material for high school and undergraduate teachers and also for the students. The chemical interactions, particularly hydrogen bonding, compose the major discussion of the text. Several contexts are used, such as acid-base chemistry, capillarity, DNA formation and genetic mutations, liquid water and its contribution in several phenomena, sweet and bitter flavor sensation chemistry, among other existing situations. All approached situations are not used as study cases, but as a way to discuss some aspects, properties and characteristics of the hydrogen bonding. Besides, the text discusses the best way for hydrogen bonding understanding in different levels. The sequence of the text set gradually the main properties of the hydrogen bonding in different contexts. The merely electrostatic model is used to explain some interesting situations. On the other hand, the text also shows that the conventional electrostatic model is not convenient to explain all phenomena, being this model questioned and rethought along the text. New arguments are used to explain the hydrogen bonding, now using the concept of electrostatic model associated to a covalent component. This approach makes more complex the original model and shows other ideas - besides the "dots¿ (X ¿ H .... X) - usually used to represent the purely electrostatics contribution of this interaction. Several properties of the hydrogen bonding using this new concept are presented and discussed along the text / Mestrado / Quimica Inorganica / Mestre em Química

The research detailed herein has been conducted in two different areas. The first research goal was to develop and study a supramolecular system coupling two light absorber units to a central metal site capable of collecting two electrons; this has been accomplished. The complex {[(bpy)2Ru(dpp)]2RhCl2}(PF6)5 was synthesized and characterized using electrochemistry and electronic absorption spectroscopy. The electrochemical properties of {[(bpy)2Ru(dpp)]2RhCl₂}(PF6)5 were probed with cyclic voltammetry and bulk electrolysis studies to investigate the behavior of the system upon two-electron reduction of the rhodium metal center. Bulk electrolysis showed that the rhodium center underwent two-electron reduction. A water modulation of product distribution for the bulk electrolysis studies was found, and the nature of this process was studied. In the presence of water, two-electron reduction of the rhodium metal center afforded a RhI complex that had lost two chloride ligands: {[(bpy)2Ru(dpp)]2RhI}+5. In the absence of sufficient water, two-electron reduction yields a breakdown of the trimetallic resulting in [(bpy)2Ru(dpp)]+2 and {[(bpy)2Ru(dpp)]RhICl₂}+. The second research goal was to develop integrated molecular modeling, synthesis, and characterization laboratory experiments, to incorporate into the undergraduate inorganic laboratory curriculum, and to evaluate and modify this curricular approach. This was accomplished with organometallic [Mo(CO)4(N-N)] complexes, where N-N is a bidentate nitrogen donor ligand. [Mo(CO)4(N-N)] complexes were selected because they were amendable to molecular modeling and could be synthesized via two synthetic routes with reasonable yields, low reaction times, and were air stable. Many of these complexes are new, so a series of [Mo(CO)4(N-N)] complexes were synthesized by either thermal or photochemical substitution reactions. The systems were characterized using cyclic voltammetry, electronic absorption spectroscopy, and ¹H NMR spectroscopy. Molecular modeling was performed on the series of [Mo(CO)4(N-N)] complexes using the CAChe software from Oxford Molecular, Ltd. These calculations typically provided reasonable structures, orbital locations, and relative orbital energies for the [Mo(CO)4(N-N)] systems. Correlations between the computational and experimental data were established. The electronic absorption spectral MLCT frequency versus calculated HOMO-LUMO energy gap, Epa versus calculated HOMO energy, E1/2red versus calculated LUMO energy, and 1H NMR chemical shift for [Mo(CO)4(1,10-phen)] and the substituted [Mo(CO)4(1,10-phen)] complexes versus ZINDO calculated partial charge were compared, where 1,10-phen = 1,10-phenanthroline. From the analyses of physical versus computational data, it was concluded that molecular modeling results are useful in predicting physical data for these complexes. The integrated molecular modeling, synthesis, and characterization experiment was developed and incorporated into the undergraduate inorganic chemistry laboratory. In both 1998 and 1999, a qualitative evaluation of student response was completed. This was done using a recorded interview technique; interviews were subsequently transcribed and rendered to extract themes. This interview style was an effective evaluation technique for this project, providing the detailed comments and student feedback that were desired. These interviews showed that the majority of the students both enjoyed this experiment and felt that the exposure to molecular modeling was worthwhile within this type of integrated lab forum. The students felt this experiment aided in their understanding of the orbital properties of inorganic systems. Student comments and suggestions facilitated modifications for future offerings in 1999 and 2000. Continued evaluation and expansion of this curricular approach are in progress. / Ph. D.

Orientador: Amadeu Moura Bego / Banca: Denis Ricardo Martins de Godoi / Banca: Luiz Henrique Ferreira / Resumo: O presente trabalho de mestrado teve como temática geral a experimentação no ensino de Química, especificamente o emprego da perspectiva investigativa de ensino no nível superior. A pesquisa visou verificar como a inserção de um erro proposital em uma atividade experimental possivelmente suscitaria no amadurecimento e formação do Espírito Científico dos alunos do curso da licenciatura. A metodologia de pesquisa teve abordagem qualitativa do tipo Estudo de Caso, e as fontes de informação foram compostas de sujeitos e documentos. Os sujeitos foram os alunos do curso de licenciatura cursando no ano de 2017 na disciplina de Laboratório de Ensino de Química Geral, e os documentos textuais foram um roteiro alterado, um formulário de proposição de hipóteses adido de um roteiro provisório, e um relatório final, no qual os alunos também propuseram um roteiro retificado para a realização da atividade experimental. Ainda, foi realizado um grupo focal com os participantes da atividade, e os alunos também responderam a um questionário, o qual providenciou suporte para a conseguinte entrevista individual. O tratamento e análise das informações coletadas se deu pela Análise de Conteúdo, para a qual foram utilizadas categorias a priori para o questionário e entrevista reflexiva, e categorias a posteriori para o grupo focal e documentos textuais. Como conclusão do estudo, concebe-se que a intervenção aqui proposta, a qual é dotada de um elemento inédito, por si só, em ação pontual, não foi ca... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The work herein presented had as general theme practical work regarding chemical education, and had its scope on the employment of inquiry-based activities at the undergraduate level. This research intended to unveil how the interposition of a purposeful error on a experimental activity could promote the formation and maturation of the scientific spirit on undergraduate students. The research methodology had used a qualitative approach, on the manners of a case study, and the information sources regarded subjects and documents. The subjects were the students undergoing the "Laboratório de Ensino de Química Geral" course, and the textual documents were a modified script, a hypothesis form coupled with a provisional script and a final report, in whose the students should add a rectified script that would allow them to perform the activity without issues. In addition, the students composed a focus group with the groups that participated in our intervention, as well as an individual questionnaire regarding aspects of nature of science. The latter provided support for the accomplishment of individual interviews with the students. The data gathering and treatment of collected data was done in the ways of the content analysis, for whose we employed a priori analytical categories for the questionnaire and individual interview, and established a posteriori categories for the focus group and textual documents. As a conclusion, we conceived that the intervention proposed on this work, w... (Complete abstract click electronic access below) / Mestre

Esta pesquisa se insere na temática de conhecimento de professores. Trata-se de um estudo de caso e a coleta e o tratamento dos dados se inserem na perspectiva da pesquisa qualitativa. Nosso intuito foi o de investigar o conhecimento pedagógico de conteúdo (CPC) de uma professora de química quando esta desenvolveu o tópico \"soluções\" nas suas turmas de Ensino Médio. Objetivou-se ainda contribuir com evidências sobre o papel do conhecimento de conteúdo no CPC. Nossos dados estão baseados em questionários, planos de aula, planejamentos, CoRes, registros audiovisuais de aulas e entrevistas. Os dados foram todos transcritos e a análise dos mesmos foi baseada na categorização das manifestações do conhecimento de professores e interpretados com relação aos correspondentes domínios dos conhecimentos de professores, conforme proposto por Rollnick et al. (2008). As interações discursivas presentes nas aulas da professora foram analisados segundo a ferramenta proposta por Mortimer e Scott (2002). A triangulação desses dados permitiu inferir sobre o conhecimento pedagógico do conteúdo dessa professora e revelaram que ela possui um CPC pouco desenvolvido com relação ao conteúdo investigado, enfatizando a memorização e cálculos em detrimento de conteúdos conceituais. Nesse estudo de caso o conhecimento do conteúdo se revelou importante e afetou outros domínios de conhecimento dessa professora, gerando reflexos no desenvolvimento do seu CPC. Concluímos pela centralidade do papel desempenhado pelo conhecimento do conteúdo no desenvolvimento do CPC e consideramos o conhecimento do conteúdo como um dos componentes essenciais do CPC. / This work has a qualitative research perspective and it is a case study related to teacher knowledge. Our focus was the pedagogical content knowledge (PCK) of a chemistry teacher during the developing of the subject matter \"solution\" at high school context. The aim of this research was also provide some evidences about the role of the subject matter knowledge (SMK) in the PCK construct. Our data are based in questionnaires, classes plans, planning, CoRes, classes video recordings and interviews. Data were all transcribed and categorized by using categories related to the manifestations of teacher knowledge and interpreted in relation to the corresponding domains of teacher knowledge, as proposed by Rollnick et al. (2008). The discursive interactions observed in classroom were analyzed by using the tool proposed by Mortimer e Scott (2002). Data triangulation allowed us conclude that the PCK of this teacher is not very well developed in relation to the subject matter investigated. The teacher emphasizes procedural approaches at the expense of conceptual understanding. During this case study the role of SMK was highlighted and it influenced others domains of this teacher knowledge, reflecting in her PCK development. We concluded by the central role performed by SMK in the PCK development and we consider SMK as one of the PCK essential components.