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100
Thales of Miletus (620BCE-540BCE)
Amber and Fur (Static Electricity)
First to Invesitgate the basic principles of the atom
NO EVIDENCE -
101
Democritus (440BCE)
Cutting the Cheese Thought Experiment
Thinks of the atom -
101
Democritus Atomic Model
Just a ball -
102
Aristotle (340BCE)
Did not believe in the atom.
Thought it put a resriction on the Gods. FIRE, AIR, WATER, EARTH -
Sir Isaac Newton
Matter is made up of atoms
Together by attractions/forces -
John Dalton
Atomic Theory Experiment
1) all matter is made up of tiny particles called atoms
2) all atoms of a given element are alike, different for different types of elements
3) compounds are formed when atoms of different elements combine in fixed proportions
4) chemical reaction is a rearragment of atoms, but the atoms themselves do not change EXPERIMENTAL EVIDENCE -
Henri Becquerel
Exposed Uranium to Sunlight
Discovers Radioactivity
Didnt know why, but he knew it happened -
J.J. Thompson
Cathode Ray experiment
Discovers electron because he realizes atoms carry charge PLUM PUDDING MODEL -
Thompson "Plum Pudding" Atomic Model
scattered protons and electrons, looks like plum pudding -
Period: to
Evolution Of Atomic Theory
-
Andrew Millikan
Oil Drip Experiment
Discovers Charge of a single electron -
Niels Bohr
Electrons have specific orbits -
Bohrs Atomic Model
specific orbits -
Ernest Rutherford
Gold Foil Experiment
Nucleus is in the center, electron are tiny and orbit
New atomic model -
Gold Foil Experiment
particles through thin gold sheet, some diflect
Discovers Nucleus -
Rutherford's Nuclear Atom Atomic Model
Nuceus, electrons surrounding -
Francis Aston
Identified Isotopes by finding masses of the same atom.
Mass Spectograph -
Erwin Schrodinger
Took the Bohr Atomic Model further.
Finds the probability of an electron in a certain orbit.
Odds of the elctrons position, not path. -
Schrodinger Quantum Mechanical Atomic model
Shaded darker for higher probability of electrons -
Chadwick Atomic Model
Nuetrons are added to the nucleus. -
James Chadwick
Discovered Neutrons
