The Atomic Theory

  • 400 BCE

    Democritus

    Democritus
    Democritus came up with the idea of the 'atom', theorizing that the whole universe is made up of tiny particles, which are indestructible and indivisible.
  • John Dalton

    John Dalton
    John Dalton discovered how to calculate atomic weight. Through this discovery, he learnt that all matter in the universe is indestructible and of constant mass.
  • J.J. Thomson

    J.J. Thomson
    J.J. Thomson was the man who discovered electrons inside the atom. This finding lead to different views of the atomic structure.
  • Albert Einstein

    Albert Einstein
    Albert Einstein demonstrated the existence of atoms and proved Democritus's theory to be correct - that the world was in fact made up of atoms, which were indestructible.
  • Ernest Rutherford

    Ernest Rutherford
    Ernest Rutherford theorized and proved that the atom was mostly empty space, filled only by the nucleus, which contained most of the weight.
  • Niels Bohr

    Niels Bohr
    Niels Bohr made the revolutionary discovery of electron orbits. This eventually lead to the configuration of shells and electrons.
  • Werner Heisenberg

    Werner Heisenberg
    Werner Heisenberg came up with the theory that the exact point of matter cannot be pinpointed. This theory was called the 'uncertainty principal'.
  • James Chadwick

    James Chadwick
    James Chadwick made the phenomenal discovery of neutrons, which, he proved made up the nucleus, and had no electrical charge.