-
Introduction of the Atom
The atom was first discovered by Democritus 442BC. He said that the atoms ar indivisible and indestructible. Democritus was the first to suggest that the atom existed but John Dalton was the first chemist to really observe and break down what the atom was in 1803.
-caption- Dalton was only an English Teacher.
- Most of the credit would go to Dalton because he broke down the atom and could describe what each part did but if it wasn't for democritus Dalton wouldn't know about the atom. -
Discovery of the Proton
-Goldstein discovered the proton when he was experimenting with the cathode-ray tube and he observed that rays were traveling in the opposite direction of the cathode-rays so he called them protons.
-Caption- Goldstein spent most of his life in the observatory doing experiments.
-During Goldsteins discovery of the prton another historical discovery was discovered and is still being used in todays society, it is called field hockey. -
Discovery of the Electron
-Thomson discovered the electron when he was performing a experiment that involved passing of elctric current through gases at low pressure.
-Caption- He won the nobel prize in physics in 1906.
- During the discovery of the Electron Thomas Edison discovered a way to patent the movie camera. -
Thomson Cathode Ray Discovery
In 1897 Thomson discovered the Electon. to do this he sealed the gases in a glass tube fitted at both ends with metal disks called electrodes. They were connected to electricity and the tube would glow. -
Robert Millikan's Charge of a Electron
In 1910 Millikan wanted to experiment to find the quantity of a electrons charge, to do this he had a oil drop experiment. In this experiment the droplets of oil would fall at different rates when he changed the voltage. -
The Discovery of the Nucleus
Rutherford proposed that the atom was mostly empty and was why it didn't reflect the alpha particles. He also said that the Nucleus was where the positive charged protons and neutral charged neutrons were located.
- Rutherford was considered the greatest experimentalist for his time.
-He basically reshaped the atomic model for everyone to see what it really was. -
Nucleus
In 1911 Rutherfords Gold Foil experiment he discovered that the Nucleus was what was deflecting the apha particles. he said that a region that has enough positive charge will deflect the alpha particles. But the neutrons weren't discovered yet untill Chadwick discovered that there are neutrons and that they are also located in the nucleus. -
Rutherford's Gold Foil Experiment Discovery
In 1911 Rutherford wanted to test the plum pudding model of atomic structure. so he came up with the Gold Foild Experiment. which would shoot a ray of alpha particles at a thin sheet of gold foil, the particles would go all the way through but some would bounce in another direction. This was because the particles were hitting the nucles. The nucleus is a tiny central core of an atom that is made up of protons and neutrons. -
Niels Bohr
He helped discover the atomic structer and the atomic bomb. He also discovery that atoms have different energy levels. Niels also won the noble prize in 1922 he worked on the Manhatten project for the atomic bomb. -
Electrons Orbitals
In 1913 Borhr's model of the elctron said that they move in a circular orbit at a fixed distance from the nucleus. He also said that these electrons moving in the orbit have a fixed energy called engergy levels.
In the picture the electrons are outside of the nucleus circling and can change energy levels. -
Discovery of the Neutron
in 1932, James Chadwick confirmed that that there was another subatomic particle called the Neutron. He discovered that the neutron was a subatomic particle with no charge but with mass nearly equal to the protons. -
Maria Goeppert-mayer
In August of 1948 Maria published her paper that had detailed evidencefor the nuclear shell, which would acount for the properties of atomic nuclei.
She was one of two women to win the nobel prize in physics.
