Atomic Model Timeline

  • 400

    Democritus

    Democritus
    Democritus believed that the atom never actually changed but instead moved about in space to create an object.
  • Dalton

    Dalton
    Dalton's atomic model did not change much from Democritus but, he came up with Dalton's Atomic Theory.
    Dalton's Atomic Theory :
    1) All matter is made of atoms. Atoms are indivisible and indestructible.2) All atoms of a given element are identical in mass and properties3) Compounds are formed by a combination of two or more different kinds of atoms.4) A chemical reaction is a rearrangement of atoms.
  • Thomson

    Thomson
    Thompson's model was said to be like plum pudding. That was said because he believed that everything was kind of stuck together.
  • Rutherford

    Rutherford
    Rutherford preformed an experiment called the Gold Foil Experiment, in this experiment he noticed that the alpha particles that he aimed at the foil was reflected in all directions. This lead him to believe that the electrons moved very quickly and around the nucleus.
  • Bohr

     Bohr
    Neil Bohr believed that each electron had a set orbit. this lead him to believe that there could pssibly be energy levels.
  • Modern

    Modern
    Through all these past descoveries and new ones comming each day the present model looks like this.