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101
Thales 620-546 BC
He was the first to investigate the basic principles of atoms. -
101
Aristotle 340 BC
He thought all things were made up of fire, air, water, and earth. -
101
Democritus 440 BC
He developed the first atomic theory. -
Newton
He contributed to Democritus' atomic theory. -
Dalton
He developed atomism, a new atomic theory. -
Becquerel
He discovered radioactivity. -
Thompson
He discovered the electron. -
Millikan
He found the charge of an electron. -
Rutherford
He discovered the proton and thought up the nucleus. -
Bohr
He came up with the electron orbit theory. -
Aston
He discovered isotopes. -
Schrodinger
He used math to determine the probability of an electron being in a certain place in an atom. -
Chadwick
He discovered the neutron.