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Democritus and Aristotle
Aristotle studided fire,water, earth, air, dryness, coldness, warmth, and moistness. He did not believe in the atom. He developed a theory based on four elemnts. FIre, water, earth, and air.
Democritus came up with atomism which is the thought that things are made up by atoms that are always in motion. He expanded Leucippus's theory. He questioned many things. He
asked that if you cut a long in half, would you be able to keep cutting the halves in half. http://www.nobeliefs.com/atom.htm -
Daton
Dalton said that atoms of the same element are identical in size, weight, properties. Atoms ca never be divided or destroyed. Atoms combine to form chemical compounds. Symbols recngnize elements. He devolped an atomic model based on different observations. http://hi.fi.tripod.com/timeline/ -
Thomson
Thomson stated that the rays inside the cathode tube were streams of particles much smaller than atoms and they were minuscule pieces of an atom. Thomson experimented with cathode ray tubes and observed them. http://atomictimeline.net/index.php -
Rutherford
He proved the positive particles were found mainly in the center of an atom callled a nucleus. He did the gold fal experiment. -
Bohr
He new that electrons orbited a nucleus. He knew they could only have a special orbit he thought they could jump orbits. Bohr created a radical model of the atom. He also observed that the electrons circled the nucleus. http://cronodon.com/Atomic/AtomTech2.html -
Heisenberg and Schrodinger
They came up with te atomic model. They created the " Schrodinger Equatian" to understand atoms. Found that electrons don't move, they show how much energy an atom has. http://hi.fi.tripod.com/timeline
