CM8003 From Alchemy to Chemistry (Summary) PDF

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Summary

Chapter Picture Name Country Work Extra information1 Empedocles GreekFour elements of Fire, Water, Air and Earth. Different ratios of elements gave different materials.2 Aristotle GreekFour qualities: Hotness, coldness, dryness and wetness3 StoicsCorrespondence between the seven metals to seven plan...

Description

Chapter

Picture

Name

Country

Work

1

Empedocles

Greek

Four elements of Fire, Water, Air and Earth. Different ratios of elements gave different materials.

2

Aristotle

Greek

Four qualities: Hotness, coldness, dryness and wetness

1

3

Stoics

4

Zosimos

Egyptian

Correspondence between the seven metals to seven planets Provided one of the first definitions of alchemy

Extra information

5

Jabir

Persian

Accepts four elements and four qualities & mercury-sulphur theory of metals

6

Zakariya

Persian

Wrote a manual of chemical practices

7

Nicholas Flammel

French

Acquired a mysterious book with a recipe to create the Philosopher's stone

8

John Dee

English

Advisor to Queen Elizabeth I

9

10

11

Francis Bacon

Paracelsus

Van Helmont

English

Scientific Method: Hypothesis and Theory

Roman

Rejected Galen's four humour, Aristotle's four elements and Geber's sulphur mercury sulphur theory. Tria Prima: Sulphur (Inflammability), Mercury (fusability, volatility), Salt (incombustibility, nonvolatility)

Belgian

Two ultimate elements: Air (does not take part in transmutation), water (can be molded into different materials). "Ferment" molds the various forms and properties of materials. Willow Tree experiment: Hypothesis, quantitative & controlled experiment.

Renaissance (1400 to 1600)

2

Sceptical Chymist: used experiments to show that Aristotle's four elements, Paracelcus's Tria Prima & Von Helmont's air and water are not elements. Defined elements and suggested that all matter are made up of corpuscles (particles) and that these gives metals their properties.

12

Robert Boyle

Irish

13

Becher

German

Terra fluida (mercurious earth), Terra lapidea (viterous earth) & Terra Pinguis (fatty earth)

14

George Stahl

German

Plogiston theory borrowed from Becher's Terra pinguis.

Age of Reason (1600 - 1750)

15

Stephen Hales

English

Pneumatic Trough

Age of Enlightenment (1700 - 1800)

16

Joseph Black

Scottish

Discoverer of CO2

17

Joseph Priestley

English

Verified that plants taken in Phlogiston and discovered de-phlogisticated air (oxygen). Discoverer of water.

2HgO > 2Hg +O2

English

Discoverer of infllammable air (hydrogen): comes from metals and that it is within phlogiston theory. Discoverer of water. Inflammable air = water + plogiston, deplogisticated air = water plogiston.

French

Discoverer of oxygen to be deplogisticated air. Used experiments of Traite Elementaire de Chimie conservation of mass to disprove plogiston theory. Tried to quantify caloric.

English

Atomic Theory: All matter are composed of solid, indivisible and indestructible atoms; in a chemical reaction, atoms are rearranged; every element has its unique kind of atom, different weights; multiple proportions where atoms combine in whole number ratios.

3 18

19

20

Henry Cavendish

Lavoisier

Dalton

Zn + HCl > ZnCl2 + H2

Definite, equivalent & multiple proportions; repulsion causes partial pressure; Book: A new system of chemical philosophy

21

English

President of the Royal Society; Voltaic Pile to split water into hydrogen and oxygen. H goes to (-) and O goes to (+); Electropositivity & electronegativity; All acids contain oxygen (wrong); acid (no oxygen, just hydrogen)

muriatic acid (spirits of salt NaCl)

Berzelius

Swedish

Characterised 2000 compounds into their composition and constituent elements; Replaced Dalton's chemical symbols with notations; Electrohemical dualism (every chemical compount has an electropositive and electronegative part).

Traite de Chimie

Prout

English

Heavier elements are built up on multiple units of hydrogen atom.

Humphry Davy

22 4

23

24

25

26

Gay-Lussac

Avogadro

Liebig

French

Measured that 2H + 1O > 2H2O (Law of combining volumes: the ratio between the P proportional to T volumes of reactants and the products are simple whole numbers)

Italian

Equal volumes of gases contain equal number of particles. Suggested that an oxygen compound contains 2 oxygen atoms.

German

Silver fulminate AgCNO; uses electrochemical dualism on organic compounds which turns out to be wrong; Kaliapparat, an instrument for organic analysis.

V proportional to N

They are isomers; different arrangment of

atoms give different properties 27

Wohler

German

Silver cyanate AgNCO; synthesis of urea, an organic compound.

28

Dumas

French

Suggested problems in the organic radicals dualism theory when electropositive H is substituted by electronegative Cl.

Laurent

French

Electrochemical dualism theory is too simplistic for organic chemistry; suggested dimer

5

29

Type' Theory -

Homologous series

30

Williamson

British

Water type; Student of Liebig

31

Gerhardt

French

Four inorganic types: Water, Ammonia, Hydrogen, Hydrogen Chloride

Italian

Promoted Avogadro's hypothesis and that equal volumes of gas can be used to calculate atomic weights; confirmed weight of oxygen to be 16.

32

Cannizaro

33

Newlands

British

Law of octaves (musical note) where every Consolation prize: 7th element has similar properties Davy medal 1887

34

Mendeleev

Russian

Periodic Table: elements arranged according to their their atomic weights which turns out to be wrong. Predicted the properties of elements that are not discovered yet, his predictions (Ga, Sc, Ge) were true.

35

Meyer

German

Same but later discovery as Mendeleev.

5

2nd prize: Davy medal 1882 with Mendeleev

36

Frankland

British

Valence Theory: All N atoms form 3 links with other atoms & all P atoms form 5 links. Combining power of the attracting element. Termed 'bond'.

37

Kekule

German

Karlsruhe Conference; From 'type' theory to valence; Carbon is tetravalent and explains about aliphatic compounds CnH2n+2; designed benzene chemical structure

38

Couper

German

Linking carbon atoms (tetravalent) and first chemical structures

Earlier

Later

39

Brown

Scottish

Design of first chemical structures

40

Van't Hoff

Dutch

In 3D, CH3R1 & CH2R1R2 have 1 isomer, CHR1R2R3 and CR1R2R3R4 have 2 isomers (not more than 2), this gives rise Chirality and optical activity (the ability to rotate plane polarised light); Chemical equilibrium is a balance of opposing reactions; change in equilibrium is constant to change in temprature.

41

Le Bel

French

Same but later discovery as Van't Hoff (more theoretical and no diagrams)

1st Chemistry Laureate 1901; Dynamique Chimique

Davy Medal in 1893 with Van't Hoff

42

Werner

Swiss-German

Coordination Chemistry: Complex ions [M(NH3)5X]n+

Nobel Prize 1913

7

43

Kirchoff & Bunsen

44

Lord Rayleigh

Discoverer of spectroscopy: using light to study atoms and molecules

English

"Contaminant in nitrogen" - 1/120 part which is Argon (spectroscopy shows that certain lines do not correspond to any gas)

Discovery of Helium by others using this technique

45

Ramsay

Scottish

Helped Lord Rayleigh in the chemical properties of Ar; isolated He from a mineral.

46

Ostwald

German

Nobel Laureate 1909

47

Carnot

French

Carnot cycle

Identified all the other noble gases

48

Joule

49

Lord Kelvin

50

Clausius

English

Wherever mechanical force is expended, an exact equivalent of heat is always obtained - First Law of Thermodynamics

Defined absolute temperature scale on the Carnot cycle

German

1st & 2nd Law: The energy of the universe is constant; entropy always increases.

51

Hess

52

Swiss

Hess's Law: If a chemical change takes place by several different routes, the overall enthalpy change is the same regardless of the route taken.

Arrhenius

Swedish

Experimentally affirmed that a solution's conductivity increased with dilution. Theoretically suggests that in a salt Nobel Laureate solution, there is a mixture of dissociated 1903 and non-dissociated parts. Arrhenius equation: K = Aexp(-Ea/RT)

Thomson

British

Discoverer of electrons using cathode ray tube. Electrification which is the splitting up of atoms; Plum pudding model.

8 53

54

Rutherford

New Zealand

Discoverer of alpha particles, beta particles and gamma rays. Plum pudding model is wrong and that positive charge is at the centre of an atom. Charge is proportional to weight.

55

Broek

Dutch

Number of possible elements = number of possible charges.

56

Moseley

British

X-ray spectrum of elements and like Mendeleev, he predicted the missing elements. Moseley's law: Frequency = (2.47E15)x(Z-1)^2.

It is the atomic number and not the atomic weight that determines the position of elements in the periodic table.

57

Soddy

58

Aston

59

Chadwick

British

Discovered isotopes, elements that have same number of protons but different number of neutrons.

Large deviations of atomic mass from integers is due to a mixture of isotopes.

Discovered neutrons

60

61

62

Abegg

Kossel

Lewis

German

The rule of eight'. E.g. NH3 (valency = 3) & NH5 (valency = 5), 3 + 5 = 8.

German

Shell structure of atoms: concept of inner shell and outer shell of electrons. The outer shell determines valency and chemistry, and has a maximum occupancy of eight. Ionic bonds: elements want to lose or gain electrons so that they can achieve a full electronic shell of a noble gas. The resultant 'ions' attract each other.

American

Covalent bond: For non-polar bond, electrons do not move away from one atom to another. Electrons can rather be shared to achieve an octet configuration. Introduction of Lewis structure (electron dot structure). Able to draw double and triple bond. Unified view of electrochemical dualism, radical theory & valence theory of organic chemistry.

63

Planck

German

Black body radiation: UV catastrophe. To Physics Nobel Prize fix this, he changed continous energy to 1918 energy that is emitted in small discrete amounts.

Einstein

German

Photoelectric effect (electrons behave like Physics Nobel Prize particles, i.e. wave-particle duality) 1921

Danish

Quantisation of L shown by constructive Discoverer of nucleus and electrons, line interference of spectra of atoms and Einstein's concept of electrons around its photons prompt Bohr's attempt at orbit and that the describing the atomic structure; able to circumferences are predict hydrogen line spectra. integer values of λ; Physics Nobel Prize 1922

9

64

65

Bohr

66

67

68

de Broglie

Schrodinger

Pauli

French

All matter have wave-like behaviour; de Broglie's wavelength

Wave theory verified by X-Ray & electron diffraction pattern in Al foil; Physics Nobel Prize 1929

Austrian

Shared physics Schrodinger wave equation (solved for Nobel prize with behaviour of electrons in hydrogen); Heisenberg electrons are 3D waves. Each 'shell' n has (formulation based on matrix algebra) n^2 orbitals. in 1933

Austrian

Pauli Exclusion Principle: To describe an electron number, we need to consider another quantum number, the spin quantum number other than n, l and m. It is either up or down. No two electron can have the same set of quantum number. Therefore each orbital can hold two electrons.

69

Born

German

Absolute square of the wavefunction is measurable: probability of finding the particle at position x within an internal of dx (probability density function)

Physics Nobel Laureate 1954

10

70

London

71

Heitler

German-American Applied the newly formulated quantum mechanics to molecules & solve the Schrodinger equation for the 2 electrons of H2. If one were to treat the 2 electrons distinguishable, energy is not low enough Birth of Quantum to form a stable bond. If they are Chemistry indistunguishable, the energy is decreased, hence explaining the stability of the covalent bond. The difference in energy is called the 'bond energy' or 'exchange German energy'.

72

Pauling

American

Translated QM to chemical language (translated London's and Heitler's paper). Created "Hybridisation". Used X-ray to study biological compounds and structures.

73

Astbury

British

Founder of molecular biology; pioneered the use of X-ray diffraction to study the structure of biological molecules and hence their functions and how they behave.

74

Franklin

British

Produced "photo 51" of DNA using x-ray diffraction.

Book: The Nature of the Chemical Bond; Chemistry Nobel Laureate 1954

Photo 51

75

76

Watson & Crick

Zewail

DNA structure

Pioneered the field of femtochemistry; watching a molecule NaI vibrates and Egyptian-American break its bond. 100 femtosecond (10E-15) lasers were used.

Awarded Nobel Prize in Physiology or medicine with Wilkins in 1962

Chemistry Nobel Prize 1999...