-
Democritus (Actually 400 B.C.)
First to break from Aristotle school of thought that all things are made of earth, wind, fire, and water. Proposed that all things are made of tiny indestructible particles called "atomos". -
John Dalton (Atom)
All matter is made of "atoms" -
J.J. Thomson (Plum Pudding)
Plum Pudding Model
Includes electrons -
Ernest Rutherford (Nucleus)
Gold Foil Experiment
Nucleus included in atom -
Neils Bohr (Orbits)
Atom model includes orbits for electrons -
Edwin Schrodinger (3-D Shells)
Electrons move in wavelike 3-D clouds of probability -
James Chadwick (Neutrons)
Neutrons discovered in the nucleus