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450 BCE
democritus
all matter around us is made of tiny particles -
daltor
all matter and elements are made up of tiny particles called atoms. Atoms are invisible. Atoms in the same element have the same amount of weight and are identical, and are different than ones in other elements. Atoms are spheres -
Thomson
Thomsons used a cathode ray tube to discover atoms had negative particles called electrons. He made the plum pudding model. -
Rutheford
The gold foil alpha experiment showed positive charge is concentrated in the nucleus. He discovered protons and nucleus. -
Bohr
He went off of Rutherford's method and said that electrons orbit the nucleus He said they have layers or specific shells they are in. -
Schrodinger
Atoms act like light and have waves. His method calculates the energy levels of electrons in the atom. He discovered atoms don't travel in a straight or fixed path. -
current
The current model is the electron cloud.