THE HISTORY OF CHEMISTRY 1

CHEMISTRY Chemistry is usually divided into 4 time periods –Pre-historic (ancient Greeks, Arabs, China –Dark Ages (Alchemy, Black Magic, 500 A.D. – 1500s –Birth of Chemistry (1600s-1800s) –Modern Chemistry (1800s-Present) 2

Pre-Historic Age 3

Three Primary Factors Based on needs and wants Needs –Shelter from the elements –Food and water –Protection Wants –A mate –Improved self-image (status, beauty) –Entertainment Needs –Shelter from the elements –Food and water –Protection Wants –A mate –Improved self-image (status, beauty) –Entertainment 4

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Humans had a many disadvantages Many animals were: Bigger Faster Stronger Had sharper teeth Had tougher skin Had better vision Had better sense of smell 6

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Stone tools technology Amazingly, stone tools can be sharper than the surgical knives used today. Knives used for cutting meat, cutting hides, cutting fibrous materials. Axes used for chopping trees. Arrowheads for killing animals at distance. All could be used for self-protection 9

Knowing what kind of rocks that were good for making stone tools was critical for survival. Flint knapping is the art and knowledge of turning stones into tools. (Our wrists are suitable for this) 10

Near volcanoes, if the melted rock is mostly silica, it can form a natural glass called obsidian. It can be worked into very sharp tools. Even today some surgeons use obsidian knives in eye surgery. 11

Apache Tears are obsidian, found in Superior 12

Fire was a huge advance in learning the chemistry of nature and improving chances of survival. 13

Learning that fire had important uses. –Warmth –Softens food and makes it easier to digest –Makes food safer to eat. –Scares away predators. –It causes changes in materials that are placed in the fire. 14

Survival with Fire Tribes who mastered the creation of fire had much better chances as survival than those who didn’t. Even Tom Hanks in Castaway realized the importance of creating a fire. 15

Copper Copper could be bent into useful shapes like needles, fasteners, nails, and weapons. Copper couldn’t be made as sharp as stone tools, but it was lighter and could be worked into a sword. It also could be shaped into armor. Copper was not a strong as stone tools, but it didn’t break so easily. It also could be molded and bent into useful shapes. The mining of copper ore and the process of turning it to metallic copper (smelting) became an important industry. 16

Swords A stone ax was a formidable weapon but it was heavy and only the end of it was dangerous. A sword is dangerous from the tip to the handle and because it is lighter it could be swung much faster. A good swordsman could usually defeat someone that had a stone ax. 17

Bronze Age If a valuable metal like copper was produced by throwing a particular colored mineral into the fire, people would have tried throwing other types of minerals into the fire and checking the results. All metals except for gold is bound with oxygen. Oxygen likes to react with things and pure metals are eventually attacked by oxygen to form an oxide. The oxide of tin (tin ore) finally got thrown into the fire and metallic tin was produced. Tin was soft and not as useful as copper; however, if it was mixed with copper and remelted, a new substance can be created. Bronze was stronger than tin or copper and resisted corrosion to water or salt water much better than copper. This became the metal of choice for the metal used on boats. 18

Bronze swords Bronze swords would break copper swords. Therefore a civilization that mastered the chemistry of mining both tin and copper. Understanding the metallurgy of combining them to produce the best alloy would have the best equipped army. 19

Iron ore Iron ore is pretty easy to recognize because of its red color. It was thrown onto hot coals too but no new metal was produced. 20

Iron Age Those who were building furnaces to heat the ore and charcoal discovered that extra air (oxygen) would make the fire and furnace hotter. Some built their furnaces on a hill or a place where the winds blew. This created hotter fires. Some built bellows that could pump oxygen into the fire and create higher temperatures. When the red soil (iron oxide) was placed into these furnaces, a new metal was discovered. 21

Iron Age Iron ore was more plentiful than tin or copper ores. Iron would corrode more than bronze but iron was stronger. Being more plentiful allowed iron to become more common place. Kettles, door hinges, wagon parts, and other useful utensils were made from it. Civilizations that could mine iron and create armour, swords, and cannons made from it, would be the ones that would survive conflicts. 22

Iron Age Dorians Barbaric Greek tribe Conquered Mycenaean Greeks Using steel weapons (Fe + C) Greeks moved into Asia Minor Finally defeated by steel equipped Israelites under King Saul 23

Blacksmiths The abundance of iron also created a new category of craftsmen known as blacksmiths. They had the tools and knowledge to forge and work iron into a multitude of useful and strong items. From nails, horseshoes, swords, anchors, and hundreds of things. 24

Not all iron is the same The amount of impurities in the iron would contribute to its qualities. Better processes in purifying was important. It was discovered that repeated heating, hammering, and cooling of iron made it less brittle. Tempered steel. This was especially important for swords. Damascus steel. 25

Weaponry It’s unfortunate, but the sophistication of a civilizations weaponry seems to be the largest factor for its survival. 26

Reflection question As we progress through time, what was one other invention that helped advance society? If man hadn’t found fire, how do you think society today would be different? 27

Development of Ancillary Skills Textiles Storage need Pottery Pyrotechnology Metallurgy (primarily copper) Fermented beverages 28

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Cooking Sterilizes Dries Drying (dehydration) Accelerated evaporation with air and sun Absorption of water with salt Controlled fermentation Wine (alcohol content prevents bacterial growth) Distillation to increase alcohol concentration Beer Cheese Separation of oils, which last longer when separated Add ingredients that prevent bacteria growth. Now we can freeze, refrigerate, freeze dry, & irradiate. 35

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The bacterium, Acetobacter, converts alcohol to acetic acid (vinegar). Oxygen encourages its growth, highlighting the importance of excluding oxygen during the wine making process. Mother of Vinegar: A slimy, gummy substance made up of various bacteria — specifically mycoderma aceti — that causes fermentation in wine and turns it into vinegar. 37

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Even in Middle-Age Europe, it was well- known that spices provide important preservation qualities. The most effective antimicrobial spices include garlic, onion, cinnamon, cloves, thyme and sage. Cloves, which have a high essential oil content, contain eugenol also present in sage and cinnamon. Allicin, present in garlic, also acts as an antimicrobial agent, as does the allyl isothiocyanate present in mustard. Thymol, present in thyme, oregano and sage, is also noted for its antimicrobial properties. Research at Kansas State University, Manhattan, has shown that cloves have a high antimicrobial effect against E. coli in ground meat. Cinnamon, garlic, oregano and sage were also shown to be effective. CH 2 =CH-CH 2 -N=C=S 40

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Egypt Practical chemical arts – very advanced Embalming and preservation of dead Metallurgical expertise Developed use of pigments Mineral and plant infusions Where does the word Chemistry come from? Kham = Egypt, derived into khemeia (Art of Egypt) Khumos = plant juice (Greek) 46

INDIA In 4000 B.C. India was working with copper, gold, paints, pottery, bricks, glass and bronze. In 2500 B.C. working with silver, lead, terra cotta, glazed pottery, gypsum cement In 1500 B. C. India was working with fermented juice (wine), tanning of leather, understood the origin of matter, the theory of atoms and molecules, atomic theory and resins, 47

Greeks The greatest philosophers Greek hypotheses Concerning the nature of matter Concerning the interactions of matter No experimentation Hindered chemical advancement 48

The Greek Elements Nature of the universe Structure of materials Philosophers (lover of wisdom) Studied the “why” Chemical theory Thales – first recorded Greek philosopher “can a substance be changed from one material into another?” Blue stone – heat became red Cu “Can any substance be changed into another?” “Are all substances different aspects of one basic material?” 49

Four Elements Fire, Air, Water, and Earth Accepted by Aristotle Combination of Properties Fire = hot and dry Air = hot and moist Water = cold and moist Earth = cold and dry 50

Aristotle Four Elements Heavenly bodies did not appear to change Properties must be different Composed of a fifth element Ether (glow) Ether was perfect, eternal, incorruptible Four earthly elements were very different These ideas lasted for 2000 years 51

Where did Aristotle come from? Plato Father claimed to be the son of Poseidon Natural philosophy was worthy of study Remove atheism and retribution Natural laws are subject to the authority of divine principles Metals are referred to as waters They melt Materials can be transmuted Founded the Athens Academy Philosophical and scientific teaching Best student was Aristotle 52

Where did Aristotle come from? Socrates Rejected experimentation Rejected proof by analogy Rejected proof by inductive reasoning Conclusions reached through mental reflection Deductive reasoning (Socratic method) Damaged the development of chemistry Sentenced to death for corrupting the youth Left star pupil Plato behind 53

Why did Aristotle’s philosophy hold sway for so long? Thoughts had an intuitive appeal Tutored the son of Philip of Macedonia Alexander the Great Conquered most of the known world Spread Greek culture and philosophy China to Spain 54

Change Persians conquer Greece Rule was harsh Scientific thought was suppressed Philosophers moved west Pythagoras went to Italy Founded a substantial school Empedocles, Sicily, eminent scholar Why was there a single element? 55

Pace Increased Climate change Extinction of many large animals Population increase Formation of large communities for survival Farming Animal domestication 56

Rise of Islam Arabs burst into western world Invaded North Africa, Egypt, and Persia In Persia – met Greek science Very interested May have been practical Stopped at Constantinople due to Greek Fire Burned in water Callinicus (Egypt) practiced khemeia Khemeia became al-kimiya in Arabic (al = the) Became Alchemy 300 BCE to 1600 CE Arabic Learning 57

Why not Europe? 300 – 1200 CE – nearly complete blank 300 – 1100 CE – height of Arabic learning Preserved and extended Greek-Egyptian Many chemical terms from this period 58

ALCHEMY 59

Theory and Practical Arts Egypt – applied chemistry Greek – theoretical approach god Thoth was source of chemical knowledge Associated with Hermes Mysticism and science relationship 60

Mysticism and Chemistry Khemeia associated with religion Practitioners were feared Priests – knowledge of the gods Astrologers – knowledge of the future Chemists – ability to change substances Used by individuals to increase power

First Practitioners Bolo of Mendes Studied changing lead (Pb) into gold (Au) 4 elements suggested the possibility Red rock gave Fe Could Fe give Au? Need the correct process 62

Alchemy Allegedly, this substance would turn cheap metals into gold. the quest for the Philosopher’s Stone (~500 – 1300 C.E.) (the elixir, the Sorcerer’s Stone) Alchemical symbols for substances… GOLDSILVERCOPPER IRON 63

transmutation: we cannot transmute elements into different elements. changing one substance into another COPPER GOLD  Philosopher’s Stone In ordinary chemical reactions… 64

Alchemy was practiced in many regions of the world, including China and the Middle East. Alchemy arrived in western Europe around the year 500 C.E. Modern chemistry evolved from alchemy. 65

Alchemy ~ 1600 ACE Mystical pseudoscience Searched for “philosopher’s stone” Some goals were transmutation, panacea and universal solvent 66

Contributions of alchemists: experimental techniques new glassware information about elements developed several alloys 67

Transmutation Greeks suggested a need for a dry powder Xerion = dry al-iksir = dry in Arabic Became elixir in English Philosopher’s stone Philosopher was a scientist 68

The Elixir Changed base metals into Au Cured all diseases Conferred immortality A new pursuit Persian Alchemist – Al-Razi Pursued medicine 69

End of Alchemy Shift from pursuit of Au to medicine Georg Bauer, German Summarized all practical knowledge of metallurgy von Hohenheim Purpose of alchemy is to prepare medicines Too much profit in pursuit of minerals and medicines to waste time on the pursuit of Au 70

BIRTH OF CHEMISTRY 71

Political Changes Constantinople – sacked by the Crusaders Most of Greek work was lost City was recovered by Greeks City was lost to Turks where it remains Compass discovered Led to great voyages of discovery Europeans no longer felt Greeks knew it all Printing press was invented Unpopular views could not be suppressed simply by not copying the work 72

Europe’s Revival Translated Arab text into Latin Gerbert (French Scholar) later Pope Sylvester II encouraged this work Others followed By 1200 alchemical knowledge was available to European Scholars Albert of Bollstadt (Albert the Great) Studied Aristotle Given credit for discovering Arsenic Roger Bacon 73

Europe’s Revival Switch to medicine in Arab world Led to decline of interest in alchemy Arabs translated many Greek texts in Arabic Military incursions by Turks and Mongols First Crusade in 1096 captured Jerusalem European presence in Middle East for 200 years Christians retook Spain Blended European and Moorish civilizations 74

Roger Bacon Today he is known for the idea that experimentation and mathematics would advance science Not widely accepted during his life Wrote a universal encyclopedia of knowledge where he described gunpowder Did not discover it Permitted its use to bring down medieval order Earliest symbol of use of technological proficiency Allowed Europe to conquer much of the world over the next 5 centuries 75

Impact of Science Polish Astronomer The Earth is not the center of the universe View held by the Greeks Accepted by Western World Nicholas Copernicus Flemish Biologist Portrayed human anatomy with great precision Refuted much of what the Greeks thought Andreas Vesalius Began the Scientific Revolution 76

MODERN CHEMISTRY 77

Modern Chemistry Astronomy careful measurement and mathematics since ancients Physics careful measurement and mathematics Since 1590 Chemistry since

Chemistry Late 18 th Century Sought an understanding of matter Philosophy changed into Science Before: Air – an element After: Air – a mixture of gases; individual gases were discovered Curiosity, careful observation, experimentation, measurement, and publication 79

Important Chemists Joseph Black – air was a mixture of gases; discovered carbon dioxide Henry Cavendish – discovered hydrogen Daniel Rutherford – discovered nitrogen Scheele, Priestly, Lavoisier discovered oxygen Antoine Lavoisier – father of modern chemistry – placed great importance on careful measurements and the Law of Conservation of Mass Joseph Proust – the Law of Definite Proportions John Dalton – atomic theory, Law of Multiple Proportion, chemical symbols A Meyer, Dimitri Mendeleev – the Periodic Table 80

Chemistry Today Physical Science Includes –Chemistry –Physics –Astronomy –Geology Biological Sciences 81

Chemistry Today Chemistry –Analytical Chemistry –Biochemistry –Inorganic Chemistry –Organic Chemistry –Physical Chemistry 82