-
400 BCE
Democritus
Democritus discovered the atomic theory, that all material bodies are made up of indivisibly small atoms. This started the study of atoms and created a blank canvas for all other discoveries. (Born 460BCE died 370BCE) -
390 BCE
Battle of the Allia
Brennus, a chieftain of the Senones of the Adriatic coast of Italy, leads an army of Cisalpine Gauls in their attack on Rome -
The French Revolution
After being found guilty of treason by the French National Convention, Citizen Capet, Louis XVI of France, is guillotined in Paris. -
John Dalton "Marble Method"
John Dalton defined the atom to be a ball-like structure because the nucleus and electrons were not discovered yet. This changed the model of atoms because the atoms within a given element are all the same size and weight, while the atoms of different elements look and are different from one other (Born 9/5/1766 and died 7/27/1844) -
Michael Faraday
Michael Faraday discovered electromagnetic induction the "induction" or generation of electricity in a wire by means of the electromagnetic effect of a current in another wire. (born on 9/22/1791, died on 8/25/1867) -
Eugen Goldstein
He discovered the proton, which changed the model of atoms for the future because it helped other people discover electrons and neutrons later on, and also showed that atoms have to have a positive charge. (Born on 9/5/1850, died on 12/25/1930) -
JJ Thomson "Plum Pudding" model
He discovered the electron, this discovery changed the model of atoms for the future because it helped people make more observations on the buildup of atoms and also led to the discovery of the neutron. (Born 12/18/1856, died 8/30/1940) -
Theodore Roosevelt became president
Theodore Roosevelt became president in 1901 -
Robert Millikan
Robert Millikan succeeded in determining the magnitude of the electron change his oil drop experiment confirmed the existence of the electron and accurately determined its charge. (Born 3/22/1868, died 12/19/1953) -
Ernest Rutherford "Nuclear model" "Jimmy Neutron" model
Ernest Rutherford found that atoms are mostly empty space and that most of their mass is from the small center nucleus. The nucleus is positively charged and surrounded by negatively charged electrons, which changed the model of the atom. (Born 8/30/1871, died 10/19/1937) -
The sinking of the Titanic
The Titanic sank in 1912, due to hitting a hidden iceberg -
Neils Bohr "solar system" model
Neils Bohr modified the atomic structure model by explaining that electrons move in fixed orbitals (shells) and not anywhere in between. He was born (10/7/1885, and died 11/18/1962) -
Werner Heisenberg
Werner Heisenberg discovered the uncertainty principle which is that the position and momentum of a particle cannot be known exactly. (Born 12/5/1901, died 2/1/1976) -
Edwin Schroedinger "electron cloud" model
he discovered and made the electron cloud method, which is a dense nucleus surrounded by a cloud of electrons at various levels in orbit. this changed how we thought about the atom because electrons were no longer seen as particles moving around a central nucleus. Born 9/12/1887, died 1/4/1961) -
James Chadwick "electron cloud model" with neutrons added
James Chadwick proved the existence of neutrons and changed how we see the atom because its neutral charge meant that the positively charged protons would not repel it. (Born 10/20/1891, died 7/24/1974) -
World War 2
World War 2 began in 1936 with a German invasion of Poland. -
U.S. Navy defeated the Japanese Navy
The U.S Navy defeats the Japanese Navy in the Battle of Midway