PRESENTATION OUTLINE
Democritus(400 bc)
Stated that all matter consisted of invisable particles called atoms
Antoine Lavaisier(1743-1794)
Discoverrd law of conservation of mass states that matter cant be created or destroyed
Law of conservation of mass(1789)
States that mass in an isolated system cant be created or destoryed
John Dalton(1803-1805)
Dicovered all items in an element are identical and compounds have a fixed ratio of atoms
Daltons Atomic Theory(1803)
States that all matter is made up of atoms
Demitri Mendelee(1834)
Russian chemist that formulated the periodic law
Ernest Rutherford(1871)
Discovered radio activity
Cathode ray tube(1895)
A glass tube with wires inserted at both ends that helps show electron movemnt
J.J. Thompson(1897)
He discovered the electron
Plum Pudding Model(1906)
Showed that elctrons were believed to be placed randomly in the atom like plum pudding
Robert Millikin(1909)
Determinded the unit charge of the electron
Gold Foil Experiment(1911)
Expected particles to pass through the foil. Positivly charged center found.
Rutherford Model(1911)
Shows that an atom is mostly empty space
Niels Bohr(1913)
He proposed a thoery for the hydrogen atom based on the quantum thoery
Bohr Planetary Model(1913)
Electrons only certain orbits around the nucleous. Light is emitted when an electron jumps from a high to a low orbit
Henry Moseley(1913)
Discoverd that atoms identity is determined by protons
Electron Cold model(1913)
Atoms model where electrons are no longer depicted as particles
Erwin Schrödinger(1926)
Combines equations for the behavior of waves to generate a mathmatical model for the distrubtion of electrons in an atom
James Chadwick(1932)
He discovered the neutron and was a collabrator of Rutherfords
Quantum Mechnical Model(1952)
A body of scientic laws
