History Of Chemistry


History of Chemistry
Introduction:
Humans have always been very curios creatures. The have always wondered about what they are and why they are here. Our limited knowledge of the environment has always urged for new things to be discovered. The desire to understand the world better has made people search for rational answers, for principles and laws. For centuries people have tried to unlock the mysterious world that surrounds them.
History:
Because myths did not explain things well enough the Greeks began to ask questions about the world around them. They did this so thoroughly and so brilliantly that the era between 600 and 400 B.C. is called the golden age of philosophy. The Greek philosophy was an attempt to find the truth about unexplained phenomena, mostly by trying to think things through, not by running experiments in a laboratory. The philosophers wanted to discover the basic nature of things and some of them believed that they could find one thing that everything else was made of. A philosopher named Thales said that this substance was water, but another named Anaximenes thought it was air. A third called Empedocles said that the world was composed of four elements: earth, air fire and water.
Aristotle became the most influential of the Greek philosophers, and his ideas dominated science for nearly two millennia after his death in 323 BC. He believed that four qualities were found in nature: heat, cold, moisture, and dryness. The four elements were each composed of pairs of these qualities; for example, fire was hot and dry, water was cold and moist, air was hot and moist, and earth was cold and dry. These elements with their qualities combined in various proportions to form the components of the earthly planet. Because it was possible for the amounts of each quality in an element to be changed, the elements could be changed into one another; thus, it was thought possible also to change the material substances that were built up from the elements-lead into gold, for example.
During this period the Greeks had laid the basic foundation for one of our main ideas about the universe. Leucippus and Democritus established the idea of the atom in an effort to figure out the ultimate composition of things. At that time there was no way to test whether atoms really existed, and more than 2000 years passed before scientists proved the theory.
Meanwhile, the Egyptians were already practicing the art of chemistry. They were mining and purifying the metals gold, silver and copper. They were making ?embalming? fluids and dyes. They called this art khemia, and it flourished until the seventh century A.D., when it was taken over by the Arabs. The Arabs changed the word khemia to alkhemia. Today our version of the word, alchemy is used to describe everything that happened in chemistry between A.D. 300 and A.D. 1600.
The main goal of the alchemists was the conversion of base metals into gold. They wanted to turn one element into another. The ancient Arabic emperors employed many alchemists to try and change mercury, copper and other less worthy metals into gold.
At almost the same time, and probably independently, a similar alchemy arose in China. Here, also, the aim was to make gold, although not because of the monetary value of the metal. The Chinese believed that gold was a medicine that could grant long life or even immortality on anyone who consumed it. As did the Egyptians, the Chinese gained practical chemical knowledge from incorrect theories.
Alchemists also tried to find the ?philosopher's stone? and the ?elixir of life?. They wanted, in other words, to discover a cure for all diseases, and a method of indefinitely prolonging life.
In the early 13th century alchemists like Roger Bacon, Albertus Magnus and Raymond Lully began to realize that the search for a philosopher's stone was useless. They believed that alchemists would better serve the world by discovering new products and new methods to improve everyday life. This started a trend in which alchemists gave up on finding the philosopher's stone. An important leader in this movement was a Swiss by the name of Theophrastus Bombastus. Bombastus felt that the object of alchemy should be the cure of the sick. He believed that salt, sulphur and mercury would give health if they were