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Period: 400 to
The Offical Atom Timespan
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450
Democritus
Theroized that everything is made of atoms, atoms are mostly empty space, and indistrucatable.
Named them atomos: not to be cut
Much observation and refelction. -
450
Aristotle
Discovered that matter must be made of smaller pieces becuase things can continously be broken into smaller pieces.
Observation ad theroies -
John Dalton
All matter made of atoms. Atoms are indivisible and indestructable.
All atoms of a given element are indentical in mass and properties.
Compounds are formed by a combination of two or more diffrent kinds of atoms.
Billiard Ball model
A chemical reaction is a rearrangment of atoms. -
Thomson
Discovered electrons, the postive charged particles and negative charged particles equal a neautral atom. -
Rutherford
Discovered the atom's nucleus and had an accurate atom model
Designed the gold foil experiment
Shot alpha particles at gold foil, the path curved indicating there was something with large postive charge.
Planetary model. -
Bohr
Expanded on Rutherford's theory
Discovered the nucleus and electrons surround it, and electrons can only move on certain paths
Outer electrons determine the elements chemical properties. The Borh Quantom model. -
Heisenberg and Schrodinger
Derived a set of equations for electrons.
Discovered the electron's spratic flight patterns.
Identified the electron cloud. Schrodinger's wave model
