Atomic Model Timeline

  • Dalton Model

    Dalton Model
    John Dalton pictures an atom as a tiny, indestructible particle, with no internal structure. Dalton came with his Atomic theory as a result of his research into gases. He discovered that certain gases only could be combined in certain proportions even if two different compounds shared the same common element or group of elements.His findings led him to hypothesize that elements combine at the atomic level Read more:
  • Thomson Model

    Thomson Model
    J.J. Thomson a British scientist, discovers the electron. that later leads to his "plum pudding" Model. He pictures electrons embedded in a sphere of positive electrical charge.In this model, the electrons were free to rotate within the blob or cloud of positive substance.
  • Hantaro Nagaoka

    Hantaro Nagaoka
    Hantaro Nagaoka suggests that an atom has a central nucleus, and electrons moves in orbits.Nagaoka rejected Thomson's model on the ground that opposite charges are impenetrable. He proposed an alternative model in which a positively charged center is surrounded by a number of revolving electrons, in the manner of Saturn and its rings.
  • Atomic Bomb

    Atomic Bomb
  • Rutherford Model

    Rutherford Model
    Ernest Rutherford a New Zealand physicist finds out that an atom has a small, dense, positively charged nucleus. Electrons move around the nucleus. The Rutherford atom has since continually been used as a symbol for atoms and even for "atomic" energy.
  • Bohr Model

    Bohr Model
    Niels Bohr"s Model shows that the electrons moves in a circular orbit around the nucleus similar in structure to the solar system, but with attraction provided by electrostatic forces rather than gravity
  • Louis de Broglie

    Louis de Broglie
    Louis de Broglie a French Physicist proposes that moving particles like electrons have some properties of waves. within a few years, experimental evidence helped to come up with the idea. It was helped by Albert Einstein, confirmed by the electron diffraction experiments of Davisson and Germer, and generalized by the work of Schrödinger.
  • Electron Cloud Model

    Electron Cloud Model
    Erwin Schrodinger develops mathematical equations to describe the motion of the electrons in atoms. His work leads to his electron cloud model.His model can not show where the electron actually is at any point in time, but it can describe where it ought to be.The possible locations of the electron predicted by Schrödinger's equation happens to be in the same locations specified in Bohr's model.
  • James Chadwick

    James Chadwick
    James chadwick, an English physicist, confirms the existence of neutrons which have no charge. Atomic nuclei contain nuetrons and positively charged protons. The electron cloud model is an atom model where electrons are no longer depicted as particles moving around the nucleus in a fixed orbit. Read more: