422-002++J+Shooshanian+and+K+Pacheco+Big+Time+Line+Project

=**Ancient Greeks and Roman Philosophers**=

world events 1.Psammetichus becoms new emperor of Egypt 2.Corinthian war 3.Babylonian Rebellion

Democritus 460 BC - 371 BC 1. He stated all matter is composed of eternal, indivisible, indestructable and indefinately small substances that cling together. 2. indivisible mean //atomos// in Greek

384 BC - 322 BC 1. Claimed there was no smallest part of matter and that different substances were made up of fire, air,earth, and water
 * Aristotle**

490-430 1.best known for creating the cosmogenic theory of the four clasic elements (fire, earth, air, water)
 * Empedocles**



=**1700-1800**=

world events 1.great Britain Established 2.Treaty of Nystad signed, ending the Great Northern war 3.The great french war

September 6, 1776 - England- to July 27, 1844 1. originated the modern atomic theory in the eraly 19th century The atomic theory was that all atoms were indestructible particles and have the same atomic weight 2. He said atoms were spheres beacuse spheres were the "divine shape" 3. Plum-pudding model, 1904, the atom is composed of electrons surrounded by posative charge
 * John Dalton**

1642-1727 1.suggested an atomic theory in which atoms combined beacause of attractive forces between them 2. described universail gravitation
 * Sir Isaac Newton**

(1743-1794) France 1. came up with the first version of the law of conservation of mass 2. recognized and named Oxygen and Hydrogen
 * Antoine-Laurent Lavoisier**

=1800-1875=

world events 1. The US buys out the French territory, (the Louisiana Purchase) 1803 2.Austrian Empire Founded 1804 3.Battle of Austerlitz 1805

March 27, 1845 - Germany - February 18, 1923 1. Won the nobel prize for discovering x-rays in 1901 2.Became a physics teacher at the University of Werzburg <-- X-ray of his wifes hand
 * Wilhelm Conrad Rontgen**

December 15, 1852 - France - August 25, 1908 1. Studied polorization of light and phosphoresence 2. He discovered uranium rays 3. He was awarded half the nobel prize, the other half went to Marie and Pierre Curie.
 * Henri Becquerel**

December 18, 1856 - England - August 30, 1940 1.Discovered the electron 2. Proposed a new model of the atom 3. Said the tiny negative charge electrons must be embedded in a cloud of posative charge since atoms have no charge. 4. This led to the "Plum-Pudding" model
 * J.J. Thompson**

=1875-1900=

world events 1.Boxer Rebellion 1898-1900 2.Klondike Goldrush 1896 3.US gains conrtol of Cuba 1898

November 7, 1867 - France - July 4, 1934 1. Most famous woman scientist 2..Discovered Polonium and Radium 3. First to use the word Radiation which describe elements that give off radiation as the nuclei break down 4. She died from overexposure to radiation in 1934
 * Marie Curie**

March 22, 1885 -1953 USA 1.Discoverd the charge of an electron is negative 2.He placed oil droplets into a chamber with a negative charge on the bottom. He saw that the particle would not fall, they would float instead.(opposite charges repel)
 * Robert A. Millikan**

August 30, 1871 - 1937 New Zealand 1. His theory tells us an atom consists of a small, dese, positively charged nucleous with electrons around it. 2.Gold foil experiement: It measured the deflection of alpha particles that were directed onto a sheet of gold foil
 * Ernest Rutherford**

=1900-1915=

world events 1.WW1 1914 2.Eastern Eurpoean Countries are founded 3.The Second Boer war ends in 1902

1877 - 1961 1. An Austrian Physicist who aquired fame from his study of quantum mechanics 2. recieved the noble prize for the Schrodinger equation in 1633
 * Erwin Schrodinger**

Oct. 20 1891 England - July 24 1974 1. famous for discovering the neutron 1932 2. became assitant director at the cavendish laboratory 3.1927, elected Fellow of the Royal Society 4. 1935 won nobel prize in physics
 * James Chadwick**

=**Albert Einstein**= 1879-1955 Germany 1. 1950-->Mass Energy Equivilence( E= //m////c//2 ) 2.1921 Noble Prize



=1915- 1950=

world events 1.Korean War 1950 2.Stalin dies 1953 3.Cold war ended

October 7, 1995 - Danmark - November 18, 1962 1. He suggested the eectrons must be orbiting the nucleous in fixed energy levels 2.introduced the idea of energy levels 3. " The Bohr Model" 4. 1909 The Rutherford- Bohr model, below, showed the plum-pudding model of the atom is incorrect
 * Niels Bohr**

5. The planetary model of the atom 1915, used as a symbol for atomic energy



1901 Germany- 1976 1. Pioneer in the field of quantum mechanics 2.head of the German nuclear energy project 3.Most known for discovering the Heisenberg uncertainty principle 4. helped contribute to the the electron cloud model in the 1900's. The cloud indicates the regions where there is a probability of finding electrons
 * Werner Heisenberg**

1873 NY- 1975 1. American Physicist who studdied electrical engineering at MIT 2.Conducted experiemnts that led to the use of tungsten as filaments in light bulbs 3.1913 invented the coolidge tube
 * William David Collidge**