Atomic Theory Timeline

  • John Dalton

    John Dalton
    John Dalton discovered that all elements always breakdown to the same components known as atoms. Atoms cannot be created or destroyed.
  • JJ Thomson

    JJ Thomson
    JJ Thomson discovered the electron. His model represents a plum cake or blueberry muffin showing a positive "cake" embed by negatively charged electrons.
  • Ernest Rutherford

    Ernest Rutherford
    Ernest Rutherford was JJ Thomson's student. He discovered that atoms are mostly empty space with nuclei that are very small.
  • Niels Bohr

    Niels Bohr
    Niels Bohr is also one of JJ Thomson's students. He discovered that electrons orbit the nucleus and can jump from level to level. He also discovered that electrons travel in a wave like pattern.
  • James Chadwick

    James Chadwick
    James Chadwick later proved the existence of neutrons (which are neutrally charged).