Timeline Chemistry

  • Democritus of Abdera
    400 BCE

    Democritus of Abdera

    Father of atomic theory
  • Aristotle
    300 BCE

    Aristotle

    Dismissed Democritus atom as worthless
  • John Dalton

    John Dalton

    The first person indentifying the possibility of an atom.His atom was indivisible,solid and sphere model
  • Joshep John Tomson

    Joshep John Tomson

    Discovered the electron.His model was with plum
  • Niels Bohr

    Niels Bohr

    Predicted that electrons travel in specified energy levels.Planetarium model.Quantum mech
  • Ernest Rutherford

    Ernest Rutherford

    Said that an atom has a small positive nucleus and the remainder is empty space.Predicted the existence of neutrons.Nuclear model
  • Werner Heisenberg

    Werner Heisenberg

    Came up with the uncertainty principle,imposible to determine position and momentum of a particular at the same time
  • James Chadwick

    James Chadwick

    Discovered neutron