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Civil War
The civil war was between Southern US states that wanted to secede and Northern US states that wanted those states a part of the Union. The war lasted 4 years. This war caused the most casualties of any war the United States has fought in. The Northern States won the war. -
Gettysburg Address
On November 19th, 1863, Abraham Lincoln was to deliver the Gettysburg Address at the National Cemetery of Gettysburg. The 273 word address, touched on the topics of racial equality and the preservation of the union, with the sacrifices involved helping to create new freedom for all. -
Law of Octaves
J.A.R. Newlands designed the Law of Octaves. There was in increase in the number of known elements and there was a need for a way to organize them. His system had vertical and horizontal rows. The vertical rows were periods and the horizontal rows were groups. The atoms were arranged based on relative atomic mass. This system had many limitations. -
President Lincoln's Assassination
While watching the play "Our American Cousin" at Ford's Theater, Abraham Lincoln was shot in the back of the head by actor and confederate sympathizer John Wilkes Booth. -
Andrew Johnson's Impeachment
Andrew Johnson was the first president to be impeached. The House of Representatives in Washington D.C. held the trial. He was tried against not following the Tenure of office act. He was not removed from office. This was during Reconstruction after the Civil War. -
Mendeleev's Period Table
Mendeleev was a Russian chemist who created a periodic table based on relative atomic mass. Physical and chemical properties of elements were put into columns. Gaps horizontally were left for elements that weren't discovered. -
Discovery of the Electron
In 1897, J.J. Thomson discovered the electron through studying the properties of the cathode ray tube, revealing that they were negatively charged. -
Spanish American War
The war was fought in Cuba and Puerto Rico. The war was between the United States and Spain. The war began with an internal explosion of the USS Maine in Cuba. The United States intervened with the Cuban war of independence. This war ended with the Treaty of Paris. -
Plum Pudding Model
The Plum Pudding Model showed that atoms have negative an positive charges. The negative charges are small compared to the entire atom. The negative particles were randomly spread throughout. Plum Pudding was thought to be similar to how the atom was structured. This model was later proved to be incorrect. -
Great San Francisco Earthquake
At roughly 5:12 a.m., a foreshock was felt throughout the San Francisco bay area.The great earthquake broke loose about 20-25 seconds later, which lasted 45-60 seconds.The earthquake leveled buildings and spawned a fire that ultimately killed over 3000 civilians. -
Gold Foil Experiment
Ernest Rutherford created the gold foil experiment at the Physical Laboratories of the University of Manchester. The gold foil experiment shot a beam of particles at a sheet of gold foil. Some particles deflected. Rutherford concluded that a nucleus of atoms were causing the deflections. -
Discovery of the Proton
After having Hans Geiger and Ernest Mansden perform the "Gold Foil Experiment," Ernest Rutherford deduced that an atom must have a very small charged nucleus orbited by smaller electrons. -
Sinking of the Titanic
The Titanic was thought to be an unsinkable ship. While sailing across the Atlantic Ocean, the ship struck an iceberg. The ship began sinking. With the little lifeboats they had, only about 500 of the 2000 on board survived. https://www.youtube.com/watch?reload=9&v=fHJ8DwXlFyQ -
Bohr's Model of the Atom
Bohr concluded that there was a center of an atom, the nucleus, that had positively charged electrons. There would be outer rings with negative electrons. A ring could only have a certain number of electrons. More electrons would have to go on additional rings. Larger atoms would have more rings. -
Mosely/Atomic Numbers
In 1913, Henry Moseley discovered that every element's identity is determined by the number of protons contained within. This allowed him to form the basis of the periodic table and to predict the existence of four new elements that were later found. -
The Beginning of World War 1
After the assassination of Archduke Franz Ferdinand, the Central Powers (Germany, Austria-Hungary, Bulgaria, and the Ottoman Empire) fought against the Allied Powers (Great Britain, France, Russia, Italy, Romania, Japan, and the United States). The war claimed the lives of over 16 million soldiers and civilians and resulted in an Allied victory on November 11, 1918 -
Schrödinger Equation
In 1926, Erwin Schrödinger published the Schrödinger equation which is used to find the allowed energy levels of quantum mechanical systems like the atom. -
The Beginning of the Great Depression
After the stock market crash of October 1929, millions of investors were wiped out. Following the wipe out, consumer spending and investment dropped, causing a decline in industry and jobs. The economic depression lasted until 1939, leaving 15 million Americans jobless. -
Discovery of the Neutron
In 1932, James Chadwick discovered the neutron after using scattering data gathered by bombarding beryllium with alpha particles. The data showed that the radiation ejected by the beryllium was a neutral particle about the mass of a proton. -
World War Two
The war started with Germany invading Poland with the support of the Soviet Union. Franc and Great Britain declared war. Poland fell very quickly. Later Japan joined the Axis powers and the United States joined the Allies powers. 35 to 60 million people died. This would help lead to the Cold War.
