FROM ALCHEMY TO SCIENCE

In the time of Aristotle, greeks spread into Egypt and Mesopotamia. And so, in the centuries that followed, the knowledge of those regions met and mixed with Greeks theories.

For instance, Egyptian metalworkers knew how to make imitation gold by mixing copper with other metals. The mixture wasn't gold, of course, but it had the color of gold. However, a Greeks theory said that gold and copper were really made of the same matter. They differed only in the “form”. So it followed that one could make gold from copper or even from lead.

Naturally, metalworkers began to try to make real gold. This was probably the beginning of a study called chemia. Exactly where this word comes from no one knows, but it is the root of our word “chemistry”.

For many centuries the students of chemia tried to make gold out of other metals. But since this was impossible by the methods they used, they always failed.

As time passed, the Arabs became great conquerors. They won control of Mesopotamia and Egypt and much more. And they took up the study of chemia, which they called al chemia (al is Arabic for “the”). This expression has come down to us as “alchemy”.

The most important Arabian alchemist was Jabir ibn Hayyan. He lived about A.D. 750 and is also known by the Latin form of his name, Geber. He seems to have made a number of discoveries about ways to prepare chemical. And it it was he who started the search for certain dry powder that came to be called the philosopher's stone. Alchemists believed that it would turn other metals into gold. And they searched for it during hundreds of years.

Arabian alchemists did discover some important new chemical substance. Among these were ammonium chloride and certain strong alkalies. Most of their time, however, was spent searching for the philosopher stone. And after the year 1000, Arabian alchemy came to an end.

However, by the 1100's Arabian books were reaching Europe. Books an alchemy (and many more) were translated into Latin. Europeans the began to search for the philosopher's stone.

Fortunatelly by the 1500's a new spirit was on the sea. There was a swiss doctor who called himself Paracelsus. He was an alchemist but not an ordinary one. He didn't think it was at all important to find methods for making gold. He thought alchemists should search for medicine to cure sickness. He was not a great scientist and some of his idea were entirely wrong. But he wanted to put an end to ancient belief's and start over. There he was right. He was also right in waiting to test ideas by experiments.

Beginning in the 1580's an Italian scientist named Galileo showed that it was very important to make accurate measurements. More could be learned in this way than in any other. He work in physics and astronomy helped to establish modern science.

Lavoisier, a French chemist, explained that a candle didn't really disappear if it burned. The carbon and hydrogen in it combined with the oxygen of the air. They formed carbon dioxide gas and water vapour. If the candle burned in a closed vessel, the weight of the candle and vessel did not change.

Chemists tried to arrange the elements in the order of their atomic weights. The most successful arranger was a Russian chemist, Dmitri I. Mendeleev. In 1869 he arranged the elements in rows and columns. He published the first periodic table, which become the basis of theoritical chemistry. The periodic table provides an easy way to show the division of the elements into two acid and base.

As chemistry had been developing so had the science of physics. Physics deals with various forms of energy, such as heat, light, electricity and magnetism. From about 1850 on, chemists began to apply the findings physics to chemistry. In this way physical chemistry was developed.