Greek Chemistry


The science of chemistry saw major advances in the era of the Ancient Greeks. Two theories arose which attempted to describe the physical and chemical properties of substances.
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Democritus


Plato (400 B.C.) described pure metals as "elemental" (stoicheia), the Greek word from which the term stoichiometry is derived.

A Greek philosopher, Democritus (ca 400 B.C.), posed one of the first theories on the elements. He was interested in the components, if any, of metals such as gold. After much investigation, he proposed that gold was "uncuttable", meaning gold contained no other simpler substance. The Greek word for this is atomos, from which the word 'atom' is derived, and is how we view the modern elements.




The most influential and popular theory was posed by Aristotle (ca 350 B.C.), and it was known as the Four Elements theory:
  1. There are four basic elements: air, earth, fire, and water.
  2. These elements interact with one another and even depend on one another (for example, wood, made from earth, will burn - create fire - but it requires air, and produces water in the process).
  3. All materials originate from one of the four basic elements.
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Aristotle's Four Elements
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Aristotle



















The element mercury (Hg) was identified, and its extraction from cinnabar (its ore) was described, although this description was likely taken from older manusctipts from Egypt or Spain.

The science of medicine also saw some advancements in this era, thanks to Hippocrates. He is what the modern "Hippocratic Oath" is named after. He also acted as an early pharmacist, prescribing willow bark as a painkiller.


Chemistry in India, China

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Kanada Vaisheshika



Interestingly, the concepts of atoms and elements were also described in Hindu and Chinese texts at approximately the same time as in Greece.

The Hindu manuscripts revealed knowledge of many metals, and a "Four Elements" theory very much equivalent to Aristotle's - around 1000 B.C.!

The Hindu philosopher Kanada Vaisheshika also derived a theory of the atom - matter being composed of indestructible spheres seven times smaller than the smallest mote of dust visible in a sun beam - around 500 B.C.

In China, many metals were recognized, along with a "Five Elements" theory, circa 350 B.C.

So, Greece was not alone in its advanced schools of thought concerning chemistry.







Alchemy


Chemistry was already studied and described by cultures such as the Greeks, Persians, Chinese, and Hindu, but was essentially absent in Europe until the Middle Ages (circa 1100 A.D.). In these cultures, advances in distillation of acids, fermentation of alcohols, production of new metals (like mercury), and discovery of new elements had occurred. Most of this information evenutally filtered into Europe via trade and cultural mingling, and translation of Arabic texts.

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Key terms:
distillation - separation of liquids by their boiling points
fermentation - digestion of starches or sugars by bacteria or yeast to produce alcohols
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An alchemical still.

In Europe, the name given to the study of chemistry was alchemy. The word alchemy originates from the Egyptian khemia, and the later Arabic al-khemia, meaning the "art of transformation".

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Alchemical Lab

Alchemy in Europe was two-faced; on one hand, there were significant advances being made in areas such as laboratory techniques, production of alcohols and mineral acids, and understanding of metal oxidation, for example.

On the other hand, there were people knowledgeable in chemistry that were using it for fraudulent purposes. Most of the 'bad' alchemists were con-artists, cheating people by coating objects in brass (a gold look-alike), wowing them with fancy pyrotechnics, or curing them with elixirs. These alchemists were eventually seen as sacrilegious, and were accused of witchcraft, among other things.

One of the most sought-after techniques was transmutation: the conversion of one element into another. Mostly, it was an attempt to create gold from less expensive metals such as lead or tin. This technique was met with failure, of course, and would not be done by chemists for another 800 or 900 years. The origins of the philosopher's stone came from the concept of transmutation - it was an alchemical substance that could turn things into gold.
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Transmutation Circle

The elixir of life was another sought-after prize. It was a cure-all potion that would extend life and rid one of disease. The concept came from the Chinese version of alchemy, and continued through the search for the Fountain of Youth.



The End of Alchemy

One of the most important alchemists was Roger Bacon, who in the late 1200's described the chemical synthesis of gunpowder (known to the Chinese for years). His ideas in science were twofold: first, sciences should become major subjects in university studies; second, chemistry was the science that linked physics to biology. He was a self-proclaimed alchemist, and suffered for it in his later years.

The conclusive end to alchemy as a descriptive term came about in the 1600's when Robert Boyle wrote his famous book, entitled "The Skeptical Chymist". Alchemy became chemistry, and thus those who took the science seriously and did so using systematic research techniques were no longer alchemists, but chemists. (The text of his book can be found here.)

Both Bacon and Boyle were influential in that they inisisted on the use of the //scientific method// to carry out research. This methodology, along with detailed record-keeping (a.k.a. lab notebooks!), laid the foundation for sound, repeatable science and eliminated once and for all the stigma of suspicion that was attached to alchemy.