What are the Stages of Chemistry?

The Historical stages of chemistry Can be divided into primitive, Greek, alchemist, renaissance, premodern and modern.

In its attempt to understand the energy that moves the world, mankind concentrated on matter to investigate what it is made of and how it reacts under various conditions.

Thanks to the instinct of conservation and later using the tools of the scientific method, from the observation and coming to create universal laws, the chemistry was developed.

From prehistory to modernity, various inquisitors and researchers provided insights for the development of an exciting hobby that soon became a science.

Main Stages of Chemistry

Primitive stage

In prehistory, the struggle for survival led man to the discovery of fire. In this natural find is located the origin of the chemistry, evidently manifesting the transformation of matter.

About 2,000 years ago, in China, products were produced that deduce the use of chemistry; The elaboration of artificial silk, gunpowder and porcelain certainly required the fusion of various elements.

Likewise in Egypt, elements used for religious rituals worked in metal were made, paintings were used, pottery was developed, fabrics were made and it was possible to evidence the use of glass.

A little later, in the era of bronze were used this and other metals such as iron.

Greek stage

Between the years 650 and 350 a.c. The chemistry was developed in Greece. Although it was Democritus and Aristotle who first approached it, it was Empedocles who stated that matter did not have a single unit but was actually made up of four elements: earth, air, water, and fire.

The study of chemistry during this period took place on a theoretical level, speaking among the positions of those who affirmed that the matter was a single unit, which was presented continuously and those who defended an atomic conception presenting, among others, the ether as An element in which resided another type of matter.

Thanks to the material compiled in the Library of Alexandria it was possible to transmit knowledge from east to west on the theorizing concerning chemistry.

Alchemist stage: 350 a.c. to 1500.d.c.

This time is full of secrecy. Chemistry continued to develop with the illusion of a humanity in search of the philosopher's stone, a substance capable of turning any metal into gold.

Alchemy began in ancient Egypt and spread to the Persian Empire, Mesopotamia, China, Arabia and Roman territory.

Unlike the Greek period, during the stage of Alchemy the theory was on the sidelines because all efforts were focused on experimentation.

While the longed for substance was never achieved, the alchemists inherited important lab techniques from the world, such as the separation of elements and distillation processes.

Renaissance stage

Without abandoning experimentation, rebirth conditioned knowledge to the use of reason. It was not only a question of observing the transformations of matter, but also of the question of chemical reactions.

During this period metallurgy and mainly pharmacology developed. Parecelso, a Swiss physician, created Iatrochemistry, which consisted of using chemistry to obtain medicines of mineral origin, as opposed to medicines of vegetable origin.

Paracelsus believed that the disease was produced by a chemical absence and to heal it was necessary to use chemicals.

Premodern stage. The Theory of Phlogiston: 1660-1770 d.c.

Created by George Stahl, the Flogist theory intended to give a scientific answer to the phenomenon of fire.

He studied the caloric phenomena that came into play in the combustion of metals, the detachment of heat, the transformation of materials into ashes and the appearance of fire with its changes of forms and colors.

The element that came off during the fire was called Flogisto and was believed to go to the atmosphere and although it was an erroneous theory was maintained during the eighteenth century, However this theory left advances in techniques and a large number of experiments.

The development of chemistry went through the study of the nature of gases also in this period. It is right here when the popular phrase takes life:"matter is not created or destroyed, it only transforms itself".

The demonstration of the existence of the atmospheric pressure occurred during this stage and in that had much to do the Irish Robert Boyle who studied the relation pressure and volume of a gas.

Stephne Halls invented the pneumatic tank and proved that it was possible to collect the gases; Thanks to this discovery the gases evolved in a reaction were collected in water and thus it was possible to study them.

Modernity: 1770 to the present

During the eighteenth and nineteenth centuries the scientists concentrated on the reactions of matter measured with quantitative techniques.

Laws such as the Law of conservation of the mass of Lavoiser, the Law of the multiple proportions of Dalton and the Law of the defined proportions of Proust were created. It was shown that the atom was real and that it was possible to determine its weight (5).

Antoine Laivosier was considered the creator of modern chemistry; Among other findings showed that water was composed of hydrogen and oxygen and refuted the theory of phlogiston with the theory of oxidation that explained the processes of combustion, respiration and calcination.

In modernity the works of Amadeo Avogadro with studies on molecules and gases, Friedrich Whöler with the synthesis of Urea, Meyer and Mendeleiv with the periodic table and August Kekulé with the tetravalence of the Carbon and the structure of Benzene, among others, were also recognized. .

Alessandro Giuseppe Volta made a battery by which an electric current was obtained; Upon deducing that matter had an electrical nature, research on electrochemical reactions became popular.

During the middle of the nineteenth century began the study of thermochemistry, ie heat processes involved in physical reactions.

Modernity also brought with it the study of atomic weight and molecular weight, and the Periodic Law of Mendeleev's chemical elements.

References

1. Bernadette B. et al. A History of Chemistry. Cambridge, Mass.: Harvard University Press, 1996. p.13-17.
2. Esteban S. S. Introduction to the History of Chemistry. National University of Distance Education. Madrid, 2011. Page 22-30
3. Lecaille C. The Phlogiston. Rise and fall of the first great chemical theory. Sciences NO. 34. April-June 1994. magazines.unam.
4. Donovan A. Lavoisier and the Origins of Modern Chemistry. Osiris Vol. 4, The Chemical Revolution: Essays in Reinterpretation (1988), pp. 214-231
5. Farrar W. V. Nineteenth-Century Speculations on the Complexity of the Chemical Elements. Volume 2, Issue 4 December 1965, pp. 297-323.