Topic 5 What is MATTER ? Early Ideas

1. Topic 5What is MATTER? Early Ideas Dr. Donna Brestensky SBU Chemistry Department Acknowledgments: J. Benington, for course text and some slides J. Miller, for some slides and pictures

2. Lecture Questions • How do study of motion and study of matter compare? • What ideas make up modern view of matter? • What types of matter were ancient people aware of? • What were Greek philosophers’ ideas about matter? • What were the significant historical chapters in humans’ study of the nature of matter? • Alchemists • Scientific Revolution • Chemical Revolution

3. How do study of motion and study of matter compare? • Newton’s theory of universal gravitation • A major triumph of early science • Gravity: a universal property of all matter • Strength of attraction a simple function of mass, regardless of material • Whatever planets are made of, they have mass! • What about properties that distinguish one type of matter from others?

4. What ideas make up our modern view of matter? Dr. Leah Frye, medicinal chemist at Schrodinger

5. A Classification of Matter: Phases • Bottle A: GAS • Bottle B: LIQUID • Bottle C: SOLID

6. A Classification Scheme for Matter

7. “The Basics”:How Do We Understand Matter? • Everything is made of atoms. • Atoms are made of protons, neutrons, and electrons. • Atoms are not all the same: each element has a different number of protons. • Atoms share electrons to form molecules. • Chemical reactions rearrange atoms in molecules. (from Benington’s text)

8. Atoms are Made of Protons, Neutrons, and Electrons. An atom is really, really, really small! Trillions on speck of dust!

9. Atoms are not all the same. • If atoms differ, they represent different elements. • Each element has a different and unique number of protons. • Usually, # of protons = # of electrons • # of neutrons varies.

10. Atoms Share Electrons

11. Atoms Share Electrons = Bonds!

12. Atoms Combine to Form Molecules. • Molecule = any combination of two or more atoms. • Most molecules are made of more than one type of atom, but not necessary (can bond 2 of same atom) • Chemical formula tells how many atoms of each element are in the molecule: • Oxygen is O2 • Water is H2O • Ammonia is NH3 • Glucose is C6H12O6

13. What Determines Chemical Properties of Each Element? • Usually, # of protons = # of electrons • Electrons tend to fill shells surrounding nucleus • More open spaces in outer shell • more covalent bonds can be made • Other aspects of atomic structure also relevant

14. Chemical Reactions Rearrange Bonding of Atoms. • Number of atoms does not change. • Reactants have same atoms as products • Only bonding arrangement of atoms changes. • Different molecules after reaction • Methane + oxygen gas  carbon dioxide + water • CH4 + 2 O2 CO2 + 2 H2O • One carbon, four oxygen, four hydrogen (before & after)

15. Stone Metals Earths Salts Air Water Fire Woods Fibers Seeds Bones Flesh Leather Pigments What Types of Matter Were Ancient People Aware of?

16. Stone • Limestone • Marble • Sandstone • Shale • Granite • Soapstone

17. Metals • Gold • Silver • Copper • Tin • Iron • Lead • Zinc

18. Where Do Metals Come From? • Few metals occur naturally in pure form • Gold, silver, copper deposits found in ancient times • Most metals occur in ores • Ores look more like earths than like metals pile of iron ore

19. Where Do Metals Come From? • Most metals occur in ores • Ores look more like earths than like metals • Ores of different metals can be distinguished lead ore

20. Where Do Metals Come From? • Most metals occur in ores • Ores look more like earths than like metals • Ores of different metals can be distinguished • Ores must be processed to yield pure metals • Only a small percentage of metal yielded copper ore; modern man’s futile attempts at smelting!

21. Alloys • Combination of metals • Better properties • Lower melting point • Stronger, less brittle • Bronze • Alloy of copper and tin

22. Metal Working in Cultural Eras • Stone age • Stone tool manufacture, no use of metals • Pre-Copper Age: found gold/silver/copper • Copper Age (4500 BC): first metal smelted • Bronze Age (3500 BC): strong copper/tin alloy • can be sharpened, easily worked • copper and tin deposits only in certain places • Iron Age (1500 BC on): • requires very hot furnace, hard to work • iron is found all over the Earth

23. Earths • Clay • Mud • Sand • Silt • Loam • Ash

24. Pottery • Fired clay • from 6500 BC? • Certain clays used • at certain temperature • for certain times • Patterned, pigmented

25. Glass • Melted sand • Certain sands used • High temperatures • Blown, molded • Earths, metals added  color, strength

26. Woods • Sycamore • Willow • Palm • Mulberry • Lotus • Cypress

27. Fibers • Grass • Cotton • Flax • Straw • Bulrushes • Hair

28. Papyrus

29. Bone and Leather

30. Arts practiced sinceearly times In addition to mentioned materials... • Pigments • Dyes • Perfumes • Fermenting drinks • Tanning

31. Summary: What types of matter were ancient people aware of? • Ancient peoples distinguished many different materials. • Engineers and artisans had developed many materials technologies. • These technologies were applied knowingly to specific materials for specific purposes.

32. What were Greek philosophers’ ideas about matter? • Thales • Anaximenes • Heraclitus • Empedocles • Aristotle • The early “Atomists”: Leucippus, Democritus

33. Nature of substances: basic element? • Anaximenes • (570 BC) • All space above • Earth is air. • Air must be • element of • universe. • Compress it to • form harder, • denser water • and Earth? • Heraclitus • (540-475 BC) • Change = Earth • characteristic • Basic element • must be • changeable. • Fire must be • that element. Thales (640–546 BC) • Basic element is water. • In greatest quantities • Found as solid, liquid, and gas

34. Empedocles – Four Elements(490 – 430 B.C.)

35. Noticed burning wood... • fire issues from it • water oozes from it/hisses • air (smoke) is produced from it • earth (ashes) remain behind

36. Four Elements Theory of Ancient Greeks(Empedocles/Aristotle) • Theory had a few main principles (incl. natural motion) • Elements contained certain mixtures of Four Qualities: Dry vs. Moist, Hot vs. Cold

37. Changing one element into another? • Changing proportions of qualities = changing one Element into another. • Elements themselves seem to be interchangeable: Water  air when it evaporates Air  water when it rains • Possible for one Earth-y substance to change into another? Idea carries over into alchemy: transmutation?

38. Leucippus and Democritus (400? BC) • Greek philosopher and his “student” • New idea: - there is a limit to how far matter can be divided - atomos: “uncuttable” particles, different shape/size

39. Atoms Now and Then…

40. What were the most significant chapters in humans’ study of the nature of matter? • Alchemy • Scientific Revolution • Chemical Revolution

41. Alchemy • Greek-influenced alchemy • Chinese alchemy • Arab/Islamic alchemy • Arab traditions passed to medieval Europeans • Paracelsus • Iatrochemists

42. Greek-influenced Alchemy(300 BC – 650 AD) Two branches: • Esoteric: religious/astrological, attempt to understand god/gods and find salvation. • Exoteric: worldly/magical, wealth-focused - Related to Four Elements/Qualities: search for the “Philosopher’s Stone” to change (transmute) base metals to gold - Sulfur and mercury were magical

43. Eastern/Chinese Alchemy • Independent of (and prior to?) Western alchemy • Chinese believed there were Five Elements: Fire, Water, Three Solids (Earth, Wood, Metal) • Search for the “Elixir of Life,” a potion for eternal life • Gold is eternal and healing, lead to medical alchemy: soluble “potable gold” is the Elixir (400 BC)

44. Arab/Islamic Alchemy(approx. 700-1200 AD) • Used “al-iksurs” (colored “seed” catalysts) in transmutation attempts. • Stressed experiment(isolate/identify/purify) • Classified materials based on physical properties as well as origin • Noted alchemists/scientists: al-Kindi, al-Razi, ibn-Sina (Avicenna), Jabir (Geber)

45. Ibn-Sina, Avicenna (980-1037) Islamic physician, poet, scientist, philosopher

46. Ibn-Sina/Avicenna • Greatest physician of his time • Believed in Four Elements, but not transmutation. • Contributions: - studied dosages and effects of drugs - had idea that chemicals maintain identity even when combined

47. Importance of Medicine • Problems: crowded, unsanitary, infested homes; contaminated food/water; low life expectancy. • Physicians in medieval Europe had more training/education than average person. - Most followed ideas of Hippocrates (460- 370 BC) and Galen (129-200 AD). - Disease = imbalance in 4 body humours.

48. Folk Medicine of The Franciscans • Roger Bacon (1267) • - medical alchemist • - distillates used as • medicine to fight • body corruption. • John of Rupescissa (1320) - alcohol contains “quintessence” for Elixir of Life - Chinese-influenced use of “potable gold” - followers distilled to get purer chemicals and thus found new substances.

49. Paracelsus (Theophrastus von Hohenheim) (1493-1541) Swiss physician, mystic, alchemist

50. Paracelsus(Theophrastus von Hohenheim) • Alchemy = study of the cosmos - he chose medicines on basis of astrological connections • Went against the dominant Galenist medical establishment • Founded science of iatrochemistry (use of chemical medicines)