Atomic Structure over the Years

By Sami Rashid
  • 322 BCE

    Leucippus of Miletis and Democritus produce first written record proposing that matter consisted of indivisible particles with nothing between them. They called this Atomos.

  • Antoine-Laurent Lavosider discovers the “Law of the conservation of mass”

  • Joseph Proust proposes “Law of definite proportions”

  • John Dalton produces his atomic theroy

  • JJ Thompson identifies electrons and produces “Plum Pudding” model of atom

  • Sir James Chadwick discovers Neutrons

  • Ernest Rutherford proposes that there is a central neuclus consisting of protons and is orbited by electrons

  • Neil Bohr proposes his version of the atomic structure