Estudo de casos na formação de professores de química

Case studies were used as teaching methodology in Chemistry teacher education. The reffered methodology consists of teaching principles of Physical Chemistry associated to biodiesel theme in an undergraduate chemistry course with pre-service teachers, who are temporary teachers in high schools in Fortaleza, Ceará, Brazil. The results showed that the methodology was well accepted by the pre-service teachers. The concepts related to Chemistry, by means of multidisciplinary science, technological and social approaches make it able to overcome and improve the present situation in public schools and provided the learning of the chemistry concepts by high school students.

Reações multicomponentes de Biginelli e de Mannich nas aulas de química orgânica experimental: uma abordagem didática de conceitos da química verde

The introduction of Mannich and Biginelli multicomponent reactions in a practical Organic Chemistry course is presented in this article. Procedures described in the literature were adapted for use under the simple conditions available in undergraduate laboratories and were selected on the basis of Green Chemistry principles and practicality of synthesis. The reactions are easy to carry out and all products are readily isolated as crystalline solids with yields ranging from moderate to high.

Metodologia de ensino jigsaw em disciplina de química medicinal

In this paper, we describe an educational experience involving the use of the jigsaw method on the Medicinal Chemistry course at the University of São Paulo, Brazil. The goal of this proposal was to investigate acceptance and contributions of the method to undergraduate chemistry teaching. Feedback on the jigsaw method collected from the focus groups and questionnaires showed that participants generally acknowledged the advantages of the jigsaw method in helping them learn the Medicinal Chemistry subject. Suggestions for improving the jigsaw method were also received from participants.

Miniprojeto para ensino de Química Orgânica Experimental baseado no acoplamento catalítico N-C promovido por micro-ondas

This paper describes a three-week mini-project for an Experimental Organic Chemistry course. The activities include N-C cross-coupling synthesis of N-(4-methoxyphenyl) benzamide in an adapted microwave oven by a copper catalyst (CuI). Abilities and concepts normally present in practical organic chemistry courses are covered: use of balances, volumetric glassware, separation of mixtures (liquid-liquid extraction and filtration), chromatographic techniques, melting point determination and stoichiometric calculations.

A teoria de pearson para a disciplina de química orgânica: um exercício prático e teórico aplicado em sala de aula

We report a didactic experience in teaching Pearson's theory (HSAB) to graduate students in organic chemistry. This approach was based on teaching students how to use computer programs to calculate frontier orbitals (HOMO-LUMO). The suggested level of calculation was a semi-empiric PM3, proving to be efficient for obtaining robust and fast numerical results that can be performed easily in the classroom. We described a practical computational exercise and asked students to compare these numerical data with qualitative analysis using valence bond theory. A comprehensive solution of this exercise is presented, aiming to support teachers in their lessons.

CÉLULAS SOLARES SENSIBILIZADAS POR CORANTES NATURAIS: UM EXPERIMENTO INTRODUTÓRIO SOBRE ENERGIA RENOVÁVEL PARA ALUNOS DE GRADUAÇÃO

An interesting practical experiment about the preparation of dye–sensitized solar cells (DSSC) using natural dyes were carried out by the undergraduate students in the chemistry course at UNICAMP . Natural dyes were extracted from blueberries (Vaccinium myrtillus L.), jabuticabas (Myrciaria cauliflora), raw and cooked beets (Beta vulgaris L.), and annattos (Bixa orellana L.), which were used to sensitize TiO2 films that composed the photoanode in the DSSC. A polymer electrolyte containing an iodide/triiodide redox couple was used in lieu of the use of liquid solutions to prevent any leakage in the devices. A maximum solar-to-electric energy conversion of 0.26 ± 0.02% was obtained for the solar cell prepared with annatto extracts. This experiment was an effective way to illustrate to the undergraduate students how to apply some of the chemical concepts that they learned during their chemistry course to produce electric energy from a clean and renewable energy source. Teachers could also exploit the basics of the electronic transitions in inorganic and organic compounds (e.g., metal-to-ligand charge transfer and ϖ-ϖ* transitions), thermodynamics (e.g., Gibbs free energy), acid–base reactions in the oxide solid surface and electrolyte, and band theory (i.e., the importance of the Fermi level energy).

AVALIAÇÃO DO USO DE PLANILHAS COMPUTACIONAIS COMO UMA FERRAMENTA DIDÁTICA EM QUÍMICA ANALÍTICA QUALITATIVA

The use of spreadsheet softwares is not widespread in Chemical Education in Brazil as a computational education tool. By its turn the Qualitative Analytical Chemistry is considered a discipline with classical and non-flexible content. Thus in this work the spreadsheet software Excel® was evaluated as a teaching tool in a Qualitative Analytical Chemistry course for calculations of concentrations of the species in equilibrium in solutions of acids. After presenting the theory involved in such calculations the students were invited to elaborate the representation of the distribution of these species in a graphical form, using the spreadsheet software. Then the teaching team evaluated the resulting graphics regarding form and contents. The graphics with conceptual and/or formal errors were returned for correction, revealing significant improvement in the second presentation in all cases. The software showed to be motivating for the content of the discipline, improving the learning interest, while it was possible to prove that even in classical disciplines it is possible to introduce new technologies to help the teaching process.

A mathematical approach to chemical equilibrium theory for gaseous systems—I: theory

Equilibrium theory occupies an important position in chemistry and it is traditionally based on thermodynamics. A novel mathematical approach to chemical equilibrium theory for gaseous systems at constant temperature and pressure is developed. Six theorems are presented logically which illustrate the power of mathematics to explain chemical observations and these are combined logically to create a coherent system. This mathematical treatment provides more insight into chemical equilibrium and creates more tools that can be used to investigate complex situations. Although some of the issues covered have previously been given in the literature, new mathematical representations are provided. Compared to traditional treatments, the new approach relies on straightforward mathematics and less on thermodynamics, thus, giving a new and complementary perspective on equilibrium theory. It provides a new theoretical basis for a thorough and deep presentation of traditional chemical equilibrium. This work demonstrates that new research in a traditional field such as equilibrium theory, generally thought to have been completed many years ago, can still offer new insights and that more efficient ways to present the contents can be established. The work presented here can be considered appropriate as part of a mathematical chemistry course at University level.

Opiniões sobre estágio curricular e prática de ensino na licenciatura em química: o caso do CEFET-PB

The Brazilian legal documents are directing the reformulation of the courses that prepare students to be teachers. Through out the country many institutions look for to fit themselves in such documents. On the other hand, other IES (Superior Education Institutions), when they are setting up such courses they looked for to be adequate to the new public politics. Based on the National Curricular Norms to form teachers for Basic Education, in tertiary level, in 2004 it was created at the CEFET-PB,the Chemistry Course (Licenciatura) to prepare people to be teachers, whose organization. This work presents the results of a research of phenomenological nature that aimed to comprehend the teachers opinions, in the range of discussions about the current politics of formation, particularly related to the CNE/CP 1 and CNE/CP 2/2002 resolutions. This work based on the curricular proposal for the Chemistry Course (Licenciatura), presents the relationship between the probationary period and the teaching practice at the CEFET-PB, in order to contribute for a reflection about these categories to clarify the teachers of the course. It started from the consideration of all changes operated in contemporary society implies changes on teacher's pedagogical practices. It was used tow instruments for the data collection: a questionnaire with open and closed questions and recordable interviews. Nine teachers form the CEFET-PB took apart and four licensed teachers. It was based in a theoretic frame as a support for discussions about the different models of teachers formation. We concluded that the representations of teachers about probationary period the practice on the activity for the teachers formation was strongly anchored in characteristic elements of the formative tendency of a institution that historically acted on a technician formation, and the results pointed to strong signs of attitudes based on a model of the technical rationality

Experimentos mentais no ensino de ciências: implementação de uma sequência didática

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

As dificuldades de implantação de atividades experimentais investigativas no ensino de Química

Dissatisfaction with certain aspects of the educational processes of the traditional teaching has always existed, and new teaching methods have been routinely studied. The experimental investigative activity is one of those alternative practices. In this type of activity the experimentation is inserted with an investigative approach, in which the student must build the concept, with proposals that represent solutions to the excited problems. In the teaching of chemistry, specifically, the need and importance of experimentation is evident, beyond motivate students, aid in the understanding of chemical concepts relating them to reality. Realizing the contributions of this methodology for teaching and learning, through this research was conducted to understand the difficulties encountered by teachers for planning and implementation of these activities in the teaching of chemistry and therefore the reasons for the dominance of traditional teaching method. The subjects were undergraduate students of chemistry course that developed and implemented differentiated learning activities for teaching and teachers who accompanied the high school students who participated in the university extension project Inclusion Science and University students and teachers from public: Teaching and Learning Chemistry focuses on research and practice”. Through the data it was possible to identify some factors that affect and hinder the implementation of experimental activities in general, not only the investigative. However, despite the difficulties experienced by undergraduates, the majority considered the activity as an alternative teaching method interesting and innovative, able to produce interest, motivation and participation of students with subsequent learning. As well as the teachers, what with all the difficulties that they had declared facing when applying experimental activities, they admitted the pedagogical... (Complete abstract click electronic access belo)

Inserção de conceitos de química verde nos componentes curriculares de laboratório de química geral

Purpose of this monograph is a critical review of articles and publications worldwide. The insertion of green chemistry concepts in the curriculum components of general chemistry lab, plays a fundamental role in the early years of a Chemistry course towards early embed the philosophy of green chemistry. The fundamental concepts of green chemistry are highlighted in order to present the huge number of challenges in developing new chemistry l in research, industry and education. The practice of a chemical that takes into account ethical environmental attitudes thought since the formation of professionals, may lead to adoption of technical microscale, replacement of toxic agents, reduction of waste generation, etc. who snore a lot with the concept of sustainability

Contribuições dos estudos de perfil dos graduandos: o caso dos cursos de licenciatura e bacharelado em Química da UNESP/Araraquara

This paper focuses on the profile of students of bachelor and teacher training degree in Chemistry and UNESP/Araraquara. Statistical and comparatives analyzes were performed with a large amount of quantitative data on those who registered and passed the entrance examinations of these courses. This information was interpreted based on the concepts of economic and cultural capital developed by Pierre Bourdieu. The first analysis concerned the approval in entrance exams and brings important conclusions regarding the aspects that favor entering university: confirmation of "preparation courses effect"; major weight of cultural capital in relation to economic capital; and observation of the phenomenon of self-selection in relation to the bachelor's under graduation course. The second analysis points to important differences in the profile of a group of students that could be considered homogeneous due to the choice of chemistry course. In addition to bringing new information on the profile of students of chemistry, our analysis has the merit of translating and quantitatively reveals ideas conveyed in common sense about passing the entrance exam.

Metodologia de ensino jigsaw em disciplina de química medicinal

In this paper, we describe an educational experience involving the use of the jigsaw method on the Medicinal Chemistry course at the University of São Paulo, Brazil. The goal of this proposal was to investigate acceptance and contributions of the method to undergraduate chemistry teaching. Feedback on the jigsaw method collected from the focus groups and questionnaires showed that participants generally acknowledged the advantages of the jigsaw method in helping them learn the Medicinal Chemistry subject. Suggestions for improving the jigsaw method were also received from participants.

Interdisciplinary project-based learning: technology for improving student cognition

The article studies a way of enhancing student cognition by using interdisciplinary project-based learning (IPBL) in a higher education institution. IPBL is a creative pedagogic approach allowing students of one area of specialisation to develop projects for students with different academic profiles. The application of this approach in the Ural State University of Economics resulted in a computer-assisted learning system (CALS) designed by IT students. The CALS was used in an analytical chemistry course with students majoring in Commodities Management and Expertise (‘expert’ students). To test how effective the technology was, the control and experimental groups were formed. In the control group, learning was done with traditional methods. In the experimental group, it was reinforced by IPBL. A statistical analysis of the results, with an application of Pearson χ 2 test, showed that the cognitive levels in both IT and ‘expert’ experimental groups improved as compared with the control groups. The findings demonstrated that IPBL can significantly enhance learning. It can be implemented in any institution of higher or secondary education that promotes learning, including the CALS development and its use for solving problems in different subject areas.