Atomic Model Developement

Timeline created by JanaeNicole_97
  • Democritus

    Their speculation on atoms, taken from Leucippus, bears a passing and partial resemblance to the nineteenth-century understanding of atomic structure that has led some to regard Democritus as more of a scientist than other Greek philosophers
  • John Dalton

    John Dalton
    studied and expanded upon this previous work and developed the law of multiple proportions: if two elements came together to form more than one compound, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small integers.
  • James Chadwick

    James Chadwick
    Chadwick’s discovery of the neutron also made it possible to produce elements heavier than uranium in the laboratory, by the capture of slow neutrons followed by beta decay.
  • J.J Thompson

    J.J Thompson
    His work put forward a new theory, that atom was made up of small particles.Thus he discovered the electrons.
  • Hantaro Nagaoka

    Hantaro Nagaoka
    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.
  • Earnest Rutherford

    Earnest Rutherford
    Proved that radioactivity involved the transmutation of one chemical element to another, and also differentiated and named alpha and beta radiation,[3] proving that the former was essentially helium ions.
  • Neils Bohr

    Neils Bohr
    As a theory, it can be derived as a first-order approximation of the hydrogen atom using the broader and much more accurate quantum mechanics, and thus may be considered to be an obsolete scientific theory.
  • Werner Heisenberg & Erwin Schrodinger

    Werner Heisenberg & Erwin Schrodinger
    Edwin Schrodinger stated that rather than electrons being distributed within an electron.