The History of Chemistry Ancient History to the Middle Ages

The History of Chemistry Part One: Ancient History to the Greek Atomic Theory

Ancient Technology First chemical processes carried out by artisans Early work involved copper Copper used from 10 000 BCE High purity Readily available Replaced by bronze A blend of copper and tin

Ancient Technology Bronze discovered independently throughout the Old World Thailand c. 4500 BCE Egypt c. 3800 BCE Greece c. 3000 BCE China c. 1800 BCE America c. 1000 CE Exports of tin from England began during the second millennium

Ancient Technology Pottery glazing Cloth dying Glass making Specific process requiring measured amounts of Silica, sodium oxide and lime Glass was water soluble until lime was added Composition of ancient glass similar to today’s glass Math and astronomy also being developed in Egypt

Ancient Technology-Key Points Chemical compounds replacing available materials Bronze, glass Specific blends of material required Specific temperatures are required Raw materials imported from great distances Astronomical and mathematical sciences developed by early Egyptians

Greek Natural Philosophy First to consider ideas scientifically Several important Greek philosophers (scientists) Thales, 625-546 BCE, began scientific thought Theory based on water Developed into four elements: Earth, Fire, Wind and Water Leucippus, c. 460 BCE, mentor to Democritus Development of the Atomic Theory

Greek Philosophers and the Atomic Theory Democritus, 460-370 BCE, developed the atomic theory Used ideas from Leucippus All matter is made of atoms (from the Greek atoma) This theory fell out of favor Revived during the Renaissance Basis for modern atomic theory

The Atomic Theory Democritus stated that all matter is made up of indivisible, indestructible particles of pure matter. These particles are atoms, from the Greek word atoma. Differences in the things we see are not because they have different atoms but different numbers of atoms arranged in different locations.

The History of Chemistry Ancient History to the Middle Ages

The History of Chemistry Part Two: Aristotle to the Middle Ages

Aristotle Most famous Greek philosopher His theories dominated science for nearly 2000 years after his death in 323 BCE Theorized each of the four elements had two of four qualities heat, cold, moisture, dryness Qualities expanded to include luster, color and malleability

Aristotle to Alchemy Aristotle believed elemental qualities could be changed Changing qualities will change elements Changing elements will result in new substances Therefore, lead can be changed into gold!

Alchemy Began in Alexandria, Egypt c. 300 BCE Aristotle’s ideas were further developed These philosophers thought all metals sought perfection Metallic perfection is (of course) gold The process could be made faster in a workshop

Alchemy Based on Aristotle’s principles and misunderstood metallurgical observations Work began in earnest c. 100 CE Dominated scientific thought for 1500 years The key ingredient was “Philosopher’s Stone” Alchemy did not work

Alchemy, the Benefits Volumes of written material Aided in understanding metallurgy Several true scientists (theologians) emerged Albertus Magnus Roger Bacon Thomas Aquinas

Alchemy World Wide Chinese alchemists from 500 CE Gold was important for health, not wealth Islamic alchemists in the 7th and 8th centuries Based on Aristotle’s theories Contact with Chinese so alchemy was pursued for health and wealth Resulted in new discoveries

Alchemy World Wide New techniques and discoveries by Arabic alchemists include: Caustic alkali Ammonium salts Improved distillation apparatus For the first time, chemical recipes required specific amounts of chemicals

Late Middle Ages Intellectual reawakening in Europe (11th century) Stimulated by contact with the Islamic culture through the Crusades Greek philosophies rediscovered by Europe translated from Arabic to Latin Many manuscripts involved alchemy Many manuscripts involved practical matters

Late Middle Ages - Practical Matters Practical matters included distillation and laboratory practices Improved Venetian glass manufacturing resulted in better distillation apparatus Better apparatus led to better technique Better technique led to collection of volatile chemicals Alcohol Mineral acids: nitric, sulfuric and hydrochloric acid. Aqua regia

Late Middle Ages - Practical Matters Knowledge of nitrates (gunpowder) brought to Europe Information came from Arabs Gunpowder was developed by the Chinese Originally used for fireworks Gunpowder industry developed by 14th century Improvement in performance paramount Used as a war commodity

Late Middle Ages - Iatrochemistry Change in focus to medicinal chemistry Iatrochemistry Resulted in a number of new medicines Laid groundwork for chemical physiology Slowed growth in fundamental chemical theories No new chemical advances until Renaissance and the 17th and 18th centuries