Atom

Atomic History Timeline

  • 450 BCE

    Empedocles

    Empedocles
    Empedocles had the idea that air, water, soil and fire were the elements from which everything else came.
  • 400 BCE

    Democritus

    Democritus
    He was the first to use the term of atoms. If you separe something a lot of times you will end up with something you can’t separate: The atom.
  • John Dalton

    John Dalton
    In 1803 John Dalton adapt Democritus’ theory that matter is composed of atoms of different masses that combine to form compounds.
  • J.J. Thomson

    J.J. Thomson
    In 1897 J.J. Thomson is known by discovering the electron and make a model of the structure of the atom.
  • Ernest Rutherford

    Ernest Rutherford
    In 1911 Ernest Rutherford make the Gold Foil Element in which he proved it needs a center, the nucleus. So, he helped to know the structure, he also discovered beta rays and alpha rays.
  • Niels Bohr

    Niels Bohr
    In 1913 Niels Bohr agreed with the model of Rutherford but he refined the model and explained why electrons don’t collide with the nucleus.
  • Louis De Broglie

    Louis De Broglie
    In 1924, De Broglie proposed that electrons and parts of the atom are like waves.
  • Erwin Schrödinger

    Erwin Schrödinger
    Erwin Schrödinger make the actual atomic model and in 1926 he make the equation to know the energy amount in electrons.
  • Werner Heisenberg

    Werner Heisenberg
    In 1927 Werner Heisenberg states that the position of a particle and momentum can't be the same.
  • James Chadwick

    James Chadwick
    In 1932 James Chadwick discovered the neutron which is one of the most important part of the atom.