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492 BCE
Democritus
Democritus came up with the discovery that all objects are made up of little indestructible and indivisible things called atoms. This was discovered by taking a simple seashell and breaking it in half. He then took that half and broke it in half over and over and over and over again until he was finally left with a fine powder. He then took the smallest piece from the powder and tried to break that but could not -
John Dalton
John Dalton came up with the discovery that when atoms of different elements are joined, separated, or rearranged chemical reactions result. He performed a series of experiments on mixtures of gases to determine what effect properties of the individual gases had on the properties of the mixture as a whole. -
J.J. Thompson
J.J. Thompson invented the Cathode Ray. This helped him discover that atoms have nucleolus's. He preformed an experiment that consisted of high energy was moved from the negative cathode plate through a vacuum sealed container to a positive plate, it created a beam of electrons. -
Lord Earnest Rutherford
Lord Earnest Rutherford confirmed that atoms have nucleolus's. This was done by conducting an experiment called the gold foil alpha particle scattering experiment. -
Niehls Bohr
Niehls Bohr discovered that atoms have heavily charged nucleus with the electrons at a distance circling around it. He then made a model to confirm his work.
