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HISTORY OF CHEMISTRY TIMELINE
Adapted from the C3P project
Rank in All
Time Most
Elegant
Experiments
p. 1 of 13
http://phys.udallas.edu/C3P/timeline/history.pdf
Rummel’s commentary is in italics.
 You will need to know the accomplishments and time
period for the individuals whose names are bold underlined
for an “A” in the Chemistry portion of 8th grade science.
The Fundamental Forces of Nature
In 1704 Isaac Newton’s publication Optics put forward the particle theory of light
based on work he had done in 1665 when he had used a prism to discover the
colors of the spectrum inside white light. He invents the reflecting telescope (1668),
establishes the binomial theorem (1665), and in his spare time co-develops calculus
(1666).
a) Newton was the last great alchemist. Chemistry begins in the ancient and
arcane arts of alchemy. Alchemists sought Transmutation and the
Touchstone: the pursuit of Midas and Eternal life.
 This Touchstone was also known as the Philosopher’s Stone.
 The original touchstone was a natural streak plate of schist from
the area around the Black Sea. The myth of Jason and the golden
Fleece originates from the manner in which gold was collected
from streams in this area.
 This magical substance could transform or transmute base metals
into gold and convert corruptible flesh into an eternal, perfect material.
 Arab Alchemists like Geber dominated “al-chymistry” from the 8th century
until the Middle Ages.
4th
b) The Hermetic arts: arcane and secret ways to transmute metals to gold
 The hermetic seal: How to create airtight jars and with better glassblowing
techniques. Perfected by the Greek-Egyptians who worshipped Hermes
the thrice-greatest.
 Guild professionals and craftsman pass along techniques for manipulating
materials as trade secrets (stained glass, sword making,
pharmacology, paper making, etc.)
 Many of the recipes were concealed in symbols or stories
(the phoenix representing cinnabar ore (HgS))
 Creating a vacuum within a sealed glass tube posed many
questions in the 17th century. Did God exist where there was nothing?
What was the mysterious cold “glow” that occurred when “evacuated” jars
were charged with static electricity? What spiritual forces were at work
here?
c) Newton’s Prism
 In 1665 he was working on improving the optics in telescopes so as to
improve his study of planetary motion. Poor lenses caused
colored rings and blurry images to be seen.
 Discovered ROYGBIV in white light by using a prism to
refract sunlight.
 Stated light was a particle or “corpuscle”, not a wave
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 Newton’s use of mathematics to develop the study of mechanics led to the
Enlightenment Period.
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
The Truth has Many Facets But it is Rational above All Else
Rationalism spelled the eventual demise of the “vital forces” concepts that
alchemy relied upon. Mechanical forces, not spiritual ones, caused
chemical reactions.
By 1800 it was clear that there were no hidden demons or spirits to be
tamed or controlled in matter.
ENLIGHTENMENT 1700 - 1820 A.D.
Enlightenment thinkers believe that science and mechanics can explain the physical
world; this moves emphasis away from humanism toward mechanism. Growth of
industry, cities, poverty, and nationalism characterizes this era. With the
establishment of the electric cell, independent experimentation with circuits, electric
fields, and resistance charges forth.
ENLIGHTENMENT WRITERS
Voltaire, 1694 - 1778, sarcastic Frenchman who wrote Candide.
Jonathan Swift, 1667 - 1745, writes Gulliver’s Travels. Satirizes complacency of the
English aristocracy.
Johann Goethe, 1749 - 1832, pens Faust, in which Dr. Faust deals with the devil for
worldly riches, fame and knowledge.
TOWARD AN IDEA OF ENERGY
1705 In response to the lack of wood for the hot fires required by smelters, brewers
and iron makers, alternative fuel sources were being tried. In England coal was a
fuel source for decades. Unfortunately, poisonous residues and thick, acrid smoke
made it a bad fuel choice for many purposes. The beer brewing industry discovered
that the roasting or slow cooking of coal in a low-oxygen environment produced
coke, a cleaner-burning, nearly pure chunk of carbon.
The removal of the dangerous or unwanted components (aromatic compounds,
sulfur) from the final product gave rise to the first industrial pollution. Coal tar and
coal gas were two of the waste products that would have to wait till the next century
to become truly useful. Using the more efficient coke as a source of fuel began a
revolution in English brewing and iron blast furnaces at this time.
1714 D.G. Fahrenheit, invents the mercury thermometer.
1729 Stephen Grey proposes that electricity can be transferred from one body to
another via a conductor. He states that electricity is on the outside of bodies.
1732 Benjamin Franklin publishes his first edition of Poor Richard’s Almanac.
1733 Charles du Fay concludes that there are two different magnetic charges: like
forces repel and opposite forces attract.
1742 Anders Celsius, first uses the Celsius scale for measuring temperature.
1740- 1751 The Crucible Steel making process perfected in Sheffield, England by
the Quaker Benjamin Hunstman. Coke fuel and clay crucibles achieved 1600 degree
C temperatures for several hours
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AGE OF ELECTRICITY
1745 Ewald von Kleist and Musschenbroek invent the Leyden Jar, a simple
electric condenser that shocks the physics world.
Ben Franklin’s 1752 kite experiment proves that lightning is a form of electricity. He
also invents the lightning rod.
In 1777 C. A. Coulomb invents the torsion balance, which he uses to measure
forces of attraction and repulsion in magnets and charged particles. He also
experiments with friction.
UP IN ARMS
1775 Peasants’ Revolt in Bohemia.
1776 American Revolution and Declaration of Independence.
1789 - 1795 French Revolution, attack on the monarchy and aristocracy by the
oppressed masses.
ENLIGHTENED THINKERS
1776 Adam Smith publishes the Wealth of Nations, which earns him the title of
Father of the Free Market Economy.
David Hume, 1711 - 1776, says cause and effect is only cause and effect if the
effect is actually caused by the cause. A skeptic, he even doubted that the sun
would rise daily.
J.J. Rousseau, 1712 - 1778, French philosopher warns that civilization has morally
corrupted man.
Immanuel Kant, 1724 - 1804, German philosopher, believes that people can only
see the world through rose-colored glasses - i.e. glasses tinted with temporal
conceptions of time and space.
RATIONAL CHEMISTRY
1761 Lomonosov conjectures the components of the atmosphere of Venus.
1774 English chemist John Priestly discovers oxygen or “dephlogisticated air”. He
Is forced to flee England to America where his friend Ben Franklin suggests that he
measure electrical forces in a sphere. He deduces the 1/r2 relationship, confirming
Coulomb’s work.
1770-1790 Frenchman Antoine Lavoisier debunked the Phlogiston Theory of
combustion and showed that flames consume oxygen and organic material to create
carbon dioxide and water. He showed that diamonds were an ore of carbon and
distinguished between elements and compounds. As a result of his careful,
quantitative measurements he proposed the idea of the Conservation of Mass in
chemical reactions. He is known as the Father of Modern Chemistry because he
helped bring Newton’s rationalism to the world of alchemy, replacing “vital spirits”
with lab data and a theoretical framework to explain it.

Ironically, he became a victim of social “enlightenment” as the monarchy was overthrown by
“rational” citizens in the bloody French Revolution. A would-be chemist whose publication he
deemed to be worthless helped to march him to the guillotine. When pleas where made to
save such a great scientist from the blade, the presiding judge declared: 'The Republic has
no need for men of science.'" Truly a loss for France and all of humanity.
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1781 William Herschel discovers Uranus.
1783 the Montgolfier brothers of France invent and successfully fly the first balloon.
1784 G. Atwood, correctly determines acceleration in a free fall to be equal to 9.8
m/s2.
INDUSTRIAL REVOLUTION
1782 James Watt made his double-acting steam engine. With this improvement the
engine had double the power with the same displacement. The Industrial Revolution
is born. “King Coal” will dominate the 19th century as it helped create the
steel necessary for large machines like the railroad and powered them with
steam.
In 1792, William Murdoch, a friend of Watt, figures out how to capture
and burn the wasted coal gas (methane created in large quantities when
roasting coal to make coke) to light his home. Improvements in production
and distribution technology and piping eventually led to London having gas
lamps in 1804 and Glasgow and Baltimore by 1817.
1791 Pierre Prevost develops principles of thermodynamics, deducing that cold is
the absence of heat.
6th
1793 Eli Whitney, American inventor of the cotton gin and interchangeable
parts for guns. “King Cotton” will dominate the Southern economy and the labor
demands of working the fields will ensure slavery continues as an institution till the
Civil War.
1798 Henry Cavendish measures the universal constant of gravitational attraction
or big “G” with an ingenious torsion balance experiment
1800 Count Alessandro Volta develops the first electric cell by alternating layers of
zinc and copper plates separated by felt soaked in brine [salt solution] (the battery).
WRITERS BLOC
The Enlightenment is the age of literary giants the likes of Byron, Shelley, Keats,
Dickens, Thoreau, Emerson, Dostoevsky, Coleridge, and Whitman.
Light Matters
1st
1800 W. Herschel, discovers infrared rays.
1803 English scientist Thomas Young conducts an experiment to disprove the
particle theory of light. He shines light through two narrow slits cut into sheet metal
and discovers that dark bands or interference patterns appear, showing that light
has a wave-like nature. His
findings are at first ridiculed until
verified and extended later in the
century.
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Atomic Theory
1803, English schoolteacher John Dalton proposed the concepts of atoms as the
fundamental unit of matter.



Built upon the previous work of the Frenchman Antoine Lavoisier on the
proportions or ratios of elements in common compounds.
4 postulates or main concepts about this basic particle of matter formed
the basis of atomic theory.
The fact that there were subatomic particles wouldn’t be discovered for
nearly 100 years.
Napoleon Bonaparte, 1769 - 1821, French leader, crowns himself Holy Roman
Emperor. He leads a series of territorial wars in Europe, which end in 1815 with the
defeat of the French army by the Russians.
War of 1812 between the U.S. and England
MUSIC FOR ALL TIME
Beethoven 1770 – 1827
Brahms 1833 – 1897
Mozart 1756 – 1791
Wagner 1813 - 1883
Tchaikovsky 1840 – 1893
Finding the Connection between Magnetism and Electricity
1820 Christian Oersted shows that electricity moving through a wire will generate a
magnetic field around that wire, the first link between electricity and magnetism. JC
Maxwell will complete the link mathematically in 1873.
In 1823 Andre-Marie Ampere, proposes that the movement of small electrical
charges is the cause of magnetic fields.
1826 George Ohm publishes a book outlining circuit behavior and resistance in
wires of varying thickness, length, and material. He finds that resistance varies
directly with length and inversely with the cross-section area of wire.
1831 Michael Faraday, a dynamo of a physicist, publishes the laws of
electromagnetic induction. He converts magnetism to electricity, inducing voltage in
wire coils. He applies the term “ion” to charged atoms. He also devises two laws of
electrolysis:
a) The mass of substance liberated at an electrode is proportional to the current
x time, or the quantity of electricity.
b) The masses of substances liberated are proportional to the chemical
equivalents of the substances.
1837 The telegraph by Samuel Morse is exhibited at College of the City of New
York. First use is in 1844.
a) Digital codes (quantatized values) were used (dot-dash or quick-long) as
electrical contacts were closed and opened, sending a signal over a powered
line.
b) Electromagnet moving a “clicker” at the receiving end sent an
audible signal.
c) As railroads expanded, telegraph lines were run parallel to them.
1838 Victoria is crowned Queen of England. Matriarch of the Victorian
Era in literature and furnishings, she ruled the British Empire for 64 years.
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Heat & Energy
1841 Meyer, Joule, and Helmholtz independently work out the law of conservation
of energy in heat transfers.
In 1843 James P. Joule discovers the mechanical equivalent of heat and
shows that a bar’s length increases when heated.
William Thomson Kelvin, “Lord Kelvin”, 1824 - 1907. A pioneer in the study
of thermodynamics, he devises the Kelvin scale of temperature with -273
degrees F as absolute zero, the point at which molecular motion stops is the
smallest possible.
1848 Revolts occur in the cities of Vienna, Paris, Berlin, Milan, Prague, and
Rome. Nationalistic and reform oriented, they [these riots] were spurred by an
economic recession.
American Civil War 1861 - 1865 Abraham Lincoln preserves the Union.
COMMUNIST ARCHITECTS
1848 Karl Marx, 1818 - 1883, and Frederick Engels, 1820 -1895, publish the
Communist Manifesto, advocating the abolition of private property and the rise of the
proletariat over the bourgeoisie middle-class. The oppressive conditions of urban
areas in the Industrial Revolution were fertile grounds for these new ideas.
Coal Tar: Industrial Waste to Industrial Chemistry.
1800-1880 Coal tar was a waste product or sludge created when coal gas
producing plants sprung up all around Europe and the US to light the urban centers.
Such sludge heavily polluted the Thames river in London.
1857 English chemist William Perkins accidentally creates the first artificial cloth
dye from the noxious waste products of roasting coal to produce coke. He was
attempting to synthesize quinine, a cure for malaria, from coal tar. Perkins went on to
modify many different compounds in coal tar to create aniline dyes. The first pinkpurple colored mauve dye was both shocking and highly desirable to consumers,
especially after Queen Victoria modeled a mauve gown in 1858.
The demand for new dyes sparked the founding fo industrial
chemistry.
a) Modifications of aniline molecules’ basic structure created
many new colors useful for dyeing cotton clothing.
b) These novel artificial colors formed the basis of industrial
chemistry as the Germans dominated the dye industry.
The European demand for stylishly dyed clothing kept the
Carbon = green
South’s cotton industry booming up till the Civil War. The German
Oxygen = blue
Sulfur = yellow
chemical conglomerates BASF, Hoechst, Bayer, Sandoz and Geigy were
Nitrogen = red
founded during this time.
c) The artificial sweetener saccharine, creosote for preserving wood timbers,
many of the unnatural colors found in children’s cereals, and surgical
disinfectants are all derived from these compounds.
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Spectral Analysis
1856 Robert Bunsen’s Burner was invented to make use of the newly
introduced coal gas in Heidelberg, Germany to generate a hotter, more
consistent flame.
1859 Bunsen and Kirchhoff, chemist and physicist, cooperate on an
experiment that shows different elements have different spectra based
on the light they emit.
a) Looked for unique light frequency patterns emitted by “excited” gases or
other hot objects placed in the flame.
b) The amount of light emitted corresponds to temperature of object, but
there is a specific light frequency spectra or “fingerprint” for each gaseous element
that is energized or “excited”.
c) Newton’s ROYGBIV could be used to identify elements and, later, compounds.
 Helium was first discovered on the sun using this method.(Helios= the Sun God)
d) Kirchhoff’s Laws are used by astronomers today.
 See p. 362-363 in Chapter 15 in your textbook.
1864 James Maxwell, in Electricity and Magnetism, predicts from his work in
electric and magnetic fields that light may be an electromagnetic wave.
a) Light has wavelength & beats/second (frequency). Speed of light = m/s = wavelength
* frequency.
b) More energy  more beats/second  more towards blue end of ROYGBIV
c) Implied the existence of EM waves beyond ROYGBIV. Radio would follow and
revolutionize communications like its predecessor, the
telegraph.
1872 American astronomer Henry Draper records the first spectral lines of a star by
using a prism to look at its wavelength components.
1876 A. G. Bell invents the telephone and the electric motor.
1847 - 1937 Thomas Edison invents the phonograph, the hydroelectric plant, and
patents over 1000 other inventions.
a) Taught during the Civil War how to be a telegraph operator by the grateful father of a
young boy that he had rescued from a rolling boxcar, Thomas Alva Edison
worked for the railroads. Many of his early inventions were related to
telegraph technology.
b) Edison nicknamed his first two children “Dot” and “Dash”
c) In 1878 Edison perfected the incandescent light bulb composed of a hot
filament (carbonized cotton) sealed in a vacuum. The base of the bulb was
sealed with metal.
d) He proposes a direct current electrical power distribution scheme while
Tesla proposes an alternating current scheme. Tesla’s idea wins for its
technical merits after a decade of conflict.
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1880 George Grubler, a German pharmacist, takes the industrial aniline textile dyes and
carefully tests them for how they stain biological specimens like plant & animal tissue
and bacteria on microscope slides. His company sells high-quality dyes that are
expertly mixed to distinguish between different tissue and cellular features that
scientists are starting to investigate. His company becomes the industrial giant
Bosch-GMBH.
Mysterious Effects
1883 Thomas Edison notices electrical current apparently traveling through a
vacuum from one end of a very hot metal wire in an incandescent bulb to the
colder metallic base. Modestly patents it as the “Edison Effect”. The
observation of these Cathode ray particles at work is a bit of pure science he
does nothing else with.
1873 Photosensitivity was first noted in1873 on crystalline selenium metal
resistor bars as sunshine hit them. These bars were used to test telegraph cables on
the Irish Transatlantic coastal station. When light shone on
the selenium bars in hermetically sealed glass tubes, the
resistance of the metal dropped and extra current flowed
through the platinum wires that were attached to them
through the glass. Only certain wavelengths of light caused
this to happen.
Electromagnetic Radiation
1887 The Michelson-Morley experiment to determine the speed of light through
“the ether” fails to detect the motion of the observer and the motion of the “ether
wind,” concluding that the speed of light in space is a constant, unaffected by an
“ether wind” [in other words, space is a vacuum].
1888 Hertz and Lodge continue Maxwell’s work on invisible EM waves and make
way for the radio to become the first broadcast medium.
1888 Nikola Tesla invents the alternating current motor in 1895. These are installed
to generate current at the Niagara Falls power station. AC power distribution beats
Edison’s DC method.
The Gilded Age
1893 Karl Benz builds the custom Mercedes.
1893 Henry Ford builds the assembly line car.
1894 Dr. Percival Lowell founds the Flagstaff Observatory in Arizona.
1896 First modern Olympic Games held in Athens.
Particle Physics Begins
1895 W. Röntgen works on the short-wave radiation, the Röntgen ray—later
shortened to the x-ray.
1896 Henri Becquerel Discovers radioactivity.
1897, Sir Joseph John Thomson, 1856 - 1940, experiments with electrical
conductivity of gases and charge and mass of electrons. He identifies the electron
with cathode rays by measuring the charge “q” to the mass “m” of the cathode-ray
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particles. He originates the “plum pudding” model of the atom, a positively charged
ball of matter embedded with negatively charged electrons.
The Cathode Ray Tube (CRT) was designed using the Edison Effect. A sealed
glass vacuum tube with a negative terminal wire (the cathode) separated by a
vacuum from a positive terminal plate (the anode). “Cathode rays” come off the
cathode (a metal filament zapped with large numbers of Coulombs of charge/sec)
and move towards the positive anode.
a) Magnetic fields can deflect the cathode ray’s
direction (North pulls electrons towards it)
b) A greenish zinc sulfide screen opposite of anode
glows green when cathode rays hit it.
 Dalton’s atomic “marbles” had been cracked
open.
c) CRT Oscilloscope invented in 1897 by German Karl Ferdinand Braun: an
analog way of viewing electrical current- visually measure highs and lows of
electrical voltage as waves as displayed on this zinc sulfide screen. He wins
Nobel prize in 1909 with G. Marconi, the inventor of “wireless telegraphy”.
d) Television and computer monitors still use CRT’s: firing electrons into red,
green, and blue (RGB) phosphorus dots covering the inner glass surface
screen surface will excite them into glowing. The electrons are steered to a
point on the screen by electromagnets in order to create images.
R + G + B glowing all at once is all at once make a white spot.
1898 Marie. and Pierre Curie discover the radioactive element radium. She wins
the Nobel prize in chemistry in 1911.
1899 Ernest Rutherford discovers alpha, beta, and gamma rays in radioactive
atoms. By 1910 he pictures the atom as a nucleus (gold-foil experiment) with orbiting
electrons. He pioneers nuclear physics by creating the first laboratory nuclear
reaction.
DAWN OF MODERN PHYSICS
The West has entered the modern era with political centralization and a
flourishing of humanism in the arts. Trouble, however, is brewing, and eventually the
world is plunged into war. Science races forward to uncover the structure of the
atom. In the search to explain the microcosm, they hope to better understand the
macrocosm, the universe.
1900 Max Planck originates the field of quantum mechanics. He solves the problem
of “ultraviolet catastrophe” by saying that light is packaged in discrete quantities
called quanta. A later discovery shows that light and matter exhibit a combination of
the properties of waves and particles. Planck’s constant measures the energy of
light by the equation E=h, where h = Planck’s universal constant and = radiation
frequency.
a) Hot bodies, such as stars or incandescent light bulb filaments, emit radiation
that can be analyzed by Kirchhoff’s spectral analyzer.
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b) It soon became apparent that all hot bodies, from gas lights to the sun,
emitted the same general distribution of intensity among light wavelengths.
c) This “black body” distribution curve was independent of what the hot object
was actually made of, with the peak of the distribution curve being dependent
upon the temperature of the object.
1901 Guglielmo Marconi uses radio to send the first wireless transatlantic Morse
code signal.
Einstein’s Revolution
1905 Albert Einstein, 1879 - 1955, publishes three papers, one of which explains
the beginning of special theory of relativity. He wins the Nobel prize for his work
explaining the photoelectric effect in light-sensitive metals such as
selenium by explaining that light could only be absorbed in discreet
energy packets (named quanta by Max Planck) and applied to light as
photons by Einstein.
Einstein’s reasoning on light quanta was this:
a) Only those photons that match selenium’s specific quanta can cause the
voltage change- the rest are “ignored”.
 Wins the Nobel prize in Physics for this work, not General Relativity.
 This idea leads to the Niels Bohr model of atomic light spectra in 1909.
 See p. 366-67 in Chapter 15 of your textbook
b) He is one of the most important physicists of the modern age, developing, for
example, a general theory of relativity which revolutionizes the concept of
gravity. He proposes that space and time are actually indivisible.
1906 Wright brothers first flight at Kittyhawk.
1910 Comet Halley passes the sun. Mark Twain, who was born during the previous
visit of Halley’s Comet, dies this year.
Artists and writers populate the first decade of the 20th century: Picasso, Pound,
Hardy, Sinclair, Chesterton, Matisse, Frank Lloyd Wright, London, Frost,
Joyce, T. S. Eliot, Huxley, Duchamp, Fitzgerald, Hemingway, Faulkner, Yeats,
and LeCoubousier.
Rutherford’s Model of the Atom
3rd
9th
1909 Robert Millikan used electric fields to deduce the charge on a single electron
by finding the equilibrium point for oil droplets of known mass and known total
charge by suspending them between charged metal plates
1909 Ernest Rutherford proposed the planetary model of the atom: a dense
positively charged nucleus orbited by lighter, negatively charged electrons filling in
the mostly empty volume. Used alpha particles shot at gold foil to detect the minute
nucleus.
The Bohr Model of the Atom
1911 Neils Bohr publishes his atomic planetary model, in which he describes the
discrete wavelength of light emitted by electrons “jumping” from one orbit to another.
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This is why electrons have to stay in orbit around the nucleus. Doesn’t yet explain
why electron energy levels are quantatized.
1912 By inventing a cloud chamber, Charles Wilson, 1869 - 1959, detects protons
and electrons by seeing the tracks that they leave behind as vapor trails.
1914 – 1919 WWI devastates the ranks of young scientists of this generation
Relativity
1915 Einstein publishes his model of gravitation--the general theory of relativity. If
light must exist at a speed of 3E8 m/s, then how can light appear to slow down to an
observer? What if space and time were curved by the presence of matter?
1923-1927 Quantum mechanics developed.
The Quantum Mechanical Model
1925 Count Louis de Broglie, postulates the wave theory of matter. Any
moving particle acts doubly and simultaneously as a wave and a particle.
He explains Bohr’s model of the quantatized atom by stating that electrons
orbit the nucleus as standing (whole quanta) waves.
1925 Austrian physicist Wolfgang Pauli states that no two electrons can
inhabit the same energy level at the same time. This is called the Pauli Exclusion
Principle
1925 Erwin Schroedinger, 1887 - 1961, develops the quantum theory of atomic
structure from a wave theory of matter.
 Electron waves existing in an orbit must form a whole number (1,2,3…) of
waves in order to exist and not cancel themselves out.
 A famous thought experiment based on quantum states: Schrödinger’s Cat
1925 Werner Heisenberg introduces the Uncertainty Principle that illustrates how
matter can exist as both a wave and a particle at the same time.
 You can never be certain as to both the exact location and the exact speed
of an electron- all you have is a region of higher probability of finding one.
 This means that electron orbitals don’t have a definite edge- they are a
swarming “probability cloud” of where you’d find an electron 90% of the time.
The Universe Expands
1925 Edwin Hubble, 1899 - 1953, claims an expanding universe, as evidenced by
the red shifted spectrum of distant galaxies. He classifies galactic systems and
proves that star systems exist beyond the Milky Way.
1925 John Baird sends the first recognizable CRT television image from a camera
across a room. The American Philo T. Farnsworth, at age 16 in 1922, had outlined
how to construct such a device. He built a much better system in 1927. The
development of television and radio makes the world a closer place. Events,
discoveries, and ideas are sent all over the globe in a matter of seconds.
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1929 Crash of American stock market followed by Great Depression.
1928 Penicillin discovered.
1929 Earth’s magnetic field reversals discovered.
1930 Dr. Percival Lowell discovers Pluto.
1930 Antiparticles proposed by P.A.M. Dirac.
1932 Sir James Chadwick discovers a chargeless particle found in nuclei called the
neutron.
1935 Nylon, the first synthetic fiber, invented.
Edwin Armstrong develops F.M. (frequency modulation) in the 1930’s.
1937 Ghandi promotes a passive resistance movement in India.
1939 Lise Meitner develops a theory of atomic fission, the splitting of an atom.
1939 Hans Bethe proposes the proton-proton cycle as the thermonuclear fusion
source of stars.
August 2,1939 Einstein writes a letter to President Roosevelt, about the
possibility of the Nazi’s making a nuclear weapon. One month later Poland is
invaded and WWII starts. Roosevelt then proposes a meager research committee to
study such a uranium-based weapon. By 1941 the Americans get serious and
develop a crash program to catch up with the Germans.
WWII 1939 - 1945.
1942 Enrico Fermi, while working on the U.S. Government
“Manhattan Project,” achieves the first sustained, controlled atomic
reaction. The project takes place under the football bleachers of the
University of Chicago’s stadium.
1945 The atomic fission bomb is dropped on Hiroshima and
Nagasaki. 140,000 people are killed in Hiroshima from a quantity of
Uranium about the size of a marshmallow being converted to pure
energy when the nuclei split.
1946 Carbon-14 dating method is developed.
1948 George Gamow, Ralph Alpher, and Hans Bethe develop the “Big Bang”
theory: all matter of the Universe was created by a primal explosion that heralded
the beginning of space-time.
1948 The transistor is invented.
THE COLD WAR
1950 Korean conflict.
1951 The first commercially built computer makes its debut.
1952 Physicists test H-Bomb in the Marshall Islands. Nuclear fission produces a
blast equivalent to several million tons of T.N.T. This bomb is 100 times more
powerful than those dropped on Hiroshima and Nagasaki.
1953 The double helix structure of DNA discovered.
POP MOVEMENT IN ART.
Warhol, Johns, Lichtenstein, Rauchenberg, Oldenburg elevate the everyday
object to the status of Art.
1957 The launch of Sputnik by the USSR propels the US into the space race.
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1959 Jack Kilby of Texas Instruments applies for a patent on the
integrated circuit where huge numbers of transistors could be shrunk
down to fit into a small area. Robert Noyce of Intel receives the patent
for this IC technology using silicon as the building block. TI and Intel
cross-license their patents and the Silicon Revolution starts.
1960 Theodore Maimen develops the laser (acronym for “light amplification by
stimulated emission of radiation”).
1961 The St. Mark's School of Texas Science Building is opened under the
leadership of Eugene McDermott and Cecil Green of Texas Instruments. The labs,
planetarium, and closed-circuit TV made it “the best science facility” in high schools
in the nation.
1963 Quasars, thought to be the most distant objects in the universe, are first
discovered.
Quarks
1964 Bell’s Theorem discovered. Philosophical foundations of quantum theory are
re-examined.
1964 Feynman, Schwinger, and Tomonaga receive the Nobel Prize for QED—
quantum electrodynamics.
1964 Murray Gell-Mann proposes quarks as the fundamental building blocks of
hadronic matter.
1967 Anthony Hewish discovers the first pulsar, code named LMG for Little Green
Men.
July 20, 1969 Neil Armstrong sets foot on the Moon. Mankind finally meets the
Man in the Moon.
1974 Weinberg, Salam, and Glashow, develop a grand unified theory, stating that
the electromagnetic and weak forces are manifestations of a single force. This unity
dissolved when the Universe cooled after the Big Bang.
1974 Experimental evidence supporting the quark model is found when the
charmed quark is discovered.
1979 Voyager 1 discovers volcanic activity on Jupiter’s moon Io.
1981 The first cases of AIDS are recognized.
1987 The Large Magellenic Cloud contains the first observable supernova since the
17th Century. Supernova 1987 sheds light on the explosive death of stars.
THE INFORMATION AGE
1990 Hubble Space Telescope (HST), window on the universe, is launched from
the space shuttle after years of delay. Optics flawed and telescope must wait two
years for Shuttle astronauts to repair it before exciting new data is gathered.
1991 The World-Wide Web (WWW) protocols are developed by Tim Berners-Lee
at CERN, the European particle accelerator center, to allow images and other
multimedia information to move over the Internet.
1992 Astronomers detect the first planets outside the solar system.
2004 The Mars Rover Opportunity detects minerals that could only have formed in
the presence of liquid water over a long period of time. The hunt for the conditions
for life on Mars intensifies.