Chemistry Teaching. Pedagogical guide that allows students to understand the essence of this science, based on certain regularities that are of vital importance.
Summary
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- 1 Pedagogical Process
- 1 Chemical reaction
- 2 Structural approach
- 3 See also
- 4 Sources
Pedagogical Process
In the Chemistry pedagogical process, the relationship established between the structure, properties and applications of substances constitutes the essence for the organization of its Teaching and Learning .
If of the substances only the properties were studied, that is to say, the manifestation of their behavior, everything would be in a phenomenological plane and the essence would not be reached, which would imply that only the effect would be observed and not the cause that originates that ” conduct”.
If one only studied the structure of substances, without linking them to properties, everything would remain on an abstract plane, without specifically observing the phenomenological.
In this way, it is impossible to verify in practice this abstract Thought, which leads to the Chemistry teaching-learning process making no sense, as this is a theoretical-experimental science.
On the other hand, if the applications of substances were studied without relating them to the properties and the latter determined by the structure, the teaching would be totally utilitarian and Pragmatic, since the students would not be able to understand the cause or the essence of the application of certain substances in life.
This would also lead to a fully reproductive and rote teaching-learning process. All of the aforementioned shows that fractionation, separation, and total isolation of one of these three categories is impossible for a better understanding and a more complete formation of a chemical picture of the world in students during the development of the teaching-educational process of Chemistry.
Chemical reaction
It is not possible, if we consider that the chemical reaction is the manifestation of the chemical properties of substances. Therefore the concept of property is essential in the study of this science, as is the concept of structure.
For a chemical reaction to occur, it is necessary to partially or totally break the chemical bonds in the reactants and to form new bonds in the products. For this reason, the concept of chemical bonding is one of the fundamentals in the study of the structure of the substance, which shows its essential character in the study of chemical reaction and in the scientific understanding of this science.
Penetrating the essence of the phenomenon, that is, why a chemical reaction occurs and how it occurs, enables students to form a scientific conception of the world and lays the groundwork for forming convictions, as well as being able to explain, argue, substantiate the occurrence of phenomena in life in general, hence the formative character in the teaching of this science.
It is important in the study of chemical reactions, how man takes advantage of the properties to apply them in certain spheres of life, so the application of the substance is essential.
For all the aforementioned, it is justified that this regularity is applicable to the study of any type of substance (inorganic or organic). For the study of Inorganic Chemistry the relationship structure-properties-applications constitutes a dialectical Unit.
Implicit in the structure-properties-applications relationship is the operationality of scientific knowledge: From living contemplation, property to abstract thought, structure and from this to practice, and application.
Structural approach
The structural, thermodynamic and kinetic approach forms the basis for the organization of teaching and learning of the chemical reaction. The substances reflect their chemical properties through reactions.
In order for the reactants to become product substances, that is, for a chemical reaction to occur, the atoms initially bound together in a certain way must be separated, at least partially, and then reunited into the products. Of course, there must be a reasonable mechanism through which the rearrangement of the Atoms can occur , otherwise the reaction would not be possible.
The fact that the atoms are initially held together in the reactants proves the existence of chemical bonds, which must break and then form new bonds in the products as stated above. All this reflects structural aspects of the chemical reaction, which are essential for understanding it. The breakdown of chemical bonds in the reactants is accompanied by an energy consumption, on the contrary, the formation of chemical bonds in the products will cause an energy release.
This energy, absorbed or released in a chemical reaction, is described by a thermodynamic function called enthalpy. In other words, thermodynamics studies, among other things, the energy processes that take place during the transformation of one substance into another. But there is another essential thermodynamic function in the study of a chemical reaction, which expresses the degree of disorder of the substances that combine and form, this function is called entropy. Changes from atomized to combined states in a chemical reaction involve the transition from a highly random state to a much more ordered state of atoms.
It is reasonable to expect that the most likely change will be the one that involves the least difference from the original disorder or randomness. From what has been said above, it can be deduced that in a chemical reaction the reacting substances can be converted into product substances, if the state of disorder and the bond energies are greater in the latter. Both influences on the direction of chemical change (the chemical reaction) are taken into account in the thermodynamic function called Gibbs free energy.
Chemical reactions tend to proceed in the direction that Gibbs free energy decreases. This constitutes a principle of the chemical reaction and expresses its spontaneity. The chemical reaction is a time-dependent process, but the evolution is such that for each moment, there is a specific structural arrangement (stable or not, but it exists) as a consequence of the inexhaustibility of matter.
Thus, for a complete understanding of what a chemical reaction is and what happens in it, it is also necessary to know the regularities of its manifestation in time, that is, its speed and mechanism. These last two concepts are studied by chemical kinetics , and of course they are essential aspects of the chemical reaction.
The chemistry is not possible to study without addressing the chemical reaction, and there are three aspects that Deplete the study of the latter: structural, thermodynamic and kinetic, then, from the foundation made earlier, which is evidenced to understand what and how a chemical reaction occurs it is necessary to establish essential, obligatory and deep links between these aspects, it is justified, in our opinion, the legal character of this regularity.
The foundation given on the two regularities with the character of law for the teaching and learning of Chemistry, shows the need to take them into account to develop any course of Chemistry at school.
