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465 BCE
Democritus
His hypothesis on atoms was created. -
Joseph Priestley
Discovered oxygen -
Antoine Lavoisier
Recognised hydrogen -
John Dalton
Proposed the theory of the atom based on the assumption that matter is made up of atoms that are indivisible and indestructible. -
J.J. Thomson
Began studying cathode rays. -
Ernest Rutherford
Discovered that the total mass of an atom is concentrated from a nucleus.