Educacion Quimica最新文献

Knowledge integration is the central duty of chemistry education and is in this context where the investigation surrounding steel corrosion inhibition bring us the opportunity to integrate knowledge from electrochemical kinetics, Organic chemistry, Instrumental analytical chemistry and electronics via the construction of a low cost potentiostat and the use of this in studies of the anticorrosive properties of atropine sulphate with carbon steel in solution. Due that this experience is going to allow the student the determination of the corrosion potential and chronoamperometric behavior of carbon steel SAE 1010 in 0.9% NaCl solution in presence and absence of atropine sulphate in a standard electrochemistry cell of three electrodes.

With educational purposes, a new chronology is introduced to address the history of chemistry around five revolutionary moments, analysing in this article only the fourth of them. Each revolution is considered in terms of the Kuhnian notion of ‘exemplar’ rather than ‘paradigm’. This approach enables the incorporation into the revolutionary process of the instruments that contributed to their establishment, as well as the concepts that were developed and the derived subdisciplines. It is recognized, beyond a dogma, the way in which several ‘hidden entities’ very important in the teaching of chemistry —such as atoms, molecules, electrons or, in this case, spin— are consolidated. It also traces the passage of the substances to the chemical species.

Using the ideas of Bakhtin and inserting them in the broader frame of discursive studies, this paper analyzes the elements of discursive genres found in chemistry textbooks texts. Chemistry twelve books were analyzed, aimed at students of the first high school series of public and private schools. Three books have been recommended by the National Textbook Program ‐ PNLD/2012 and chosen by a large number of public school teachers. The object of the study was content Chemical Bonds. It was possible to identify recaps, calls and metaphors (the didactic genre elements); description, classification, explanation and definition (the scientific genre elements). The context element was just described in the analyzed books. The use of metaphor was predominant in the book H.

The paper presents a new reading on the construction of acid‐base theory in the twentieth century, more specifically the participation of S.A. Arrhenius, J.N. Bronsted, T.M. Lowry and G.N. Lewis. Along the historiographical review confronted naive views of the nature of science in order to achieve a better reflection on the scientist's role in science. The reading will provide a rethink about the importance of the history of chemistry in the classroom.

From different spaces it has been stated that the training in competences would seem to be the challenge of High Education. In this teaching model, not only is the understanding of the conceptual content of the disciplines important, but also the acquisition of the complex skills needed to develop competently.

This paper presents a proposal for the experimental part of a university course of Organic Chemistry based on the approach of teaching by competences. We believe that, through its implementation, competencies such as: organization and decision making, manual skills, investigative procedures and attitudes, conceptual understanding, social attitudes and information management, are promoted. Students must design a work plan whose objective is the isolation and purification of a natural product, using all the theoretical tools studied and the materials and reagents available. Subsequently they must present it in oral and written form, execute it and make a final report (written and oral) in which the results are communicated, analyzed and discussed.

The experiences showed a greater motivation of the students and an environment of great potentiality to favor the acquisition of scientific-technological competences. These kinds of experiences are transferable to other disciplines that require experimental work.

Research is one of the necessary elements to build up knowledge; for this reason, the career of nutrition at Mariano Galvez University has implemented research as an important component of the course of analytical chemistry. During this process, the impact of scientific involvement is evaluated as part of a regular course and it allows students to develop a research as a product of their imagination and curiosity.

In this paper, an approach to the removal of the eriochrome black T in an actual effluent (generated from the test to determine the water hardness by complexometric titration) using perlite modified with orthophenanthroline by the adsorption technique is proposed. A preliminary assessment of the removal of eriochrome black T in a synthetic effluent (aqueous solution of eriochrome black T) was executed for subsequent application of the optimized conditions in actual residual water (titration residue of complexation). The removal of dye at pH 10, the natural pH of the actual effluent, was not significant reaching 8.12% of color removal, on the other hand, the removal of dye at pH 3 achieved the maximum color removal (100%), indicating that the eriochrome black T interacts more effectively with the adsorbent at acidic pH (pH 5 or 3), and more efficiently at pH 3. Therefore, by the results obtained under conditions established in this present study were concluded that expanded perlite (an amorphous and naturally acidic aluminosilicate) modified with orthophenanthroline (a Bronsted base) is an easy to prepare, cheap and effective material for removal of acid dyes (eriochrome black T) applied to residues containing eriochrome T black generated during practical chemistry classes.

This paper presents a task designed to introduce 9^th grade students (14-15 years old) to planning investigations in the Chemistry laboratory. We used a context related to everyday life: an enterprise committee has just launched a campaign in schools in which they ask students to help them to unmask another who has announced a very efficient detergent called Limpics. To help students in planning the investigation, they were provided with coloured cards containing some questions. Their answers to these questions following a particular order will compose the planning. The analysis consists of examining students’ written designs (N = 20) depending on their content and adequacy to solve the investigation. The main results point to short and little precise designs.

Physicochemistry's contents are considered as of little application in the future, and so a lot of the students direct their efforts towards a superficial learning. Problem-based learning (PBL) is a methodological strategy that seeks to stimulate the need of knowing in students and it is used as a mean to acquire knowledge and apply them to solve a real or fictitious problem. The purpose of this article is to describe the results of an experience in which PBL was used as a complement of traditional teaching in three student cohorts. Two instances of qualitative evaluation and three of quantitative evaluation were done. Results showed a high qualitative evaluation, emphasizing the studentś satisfaction with the close integration of theoretical and practical contents. At the same time, the group quantitative achievements were very encouraging, even though the individual performance of the group members did not reflect the same. In conclusion, the adoption of PBL as a complement to traditional teaching is an educational investment that is fruitful at least in the short and medium term, despite the initial resistance of the students and the time and effort demanded to teachers and students.