Atomic Structure Timeline

By bryanlim
  • Oct 21, 1000

    Democritus

    "by convention bitter, by convention sweet, but in reality atoms and void"

  • Isaac Newton

    Proposed a mechanical universe with small solid masses in motion.

  • John Dalton

    Proposed an "atomic theory" with spherical solid atoms based upon measurable properties of mass.

  • Michael Faraday

    Studied the effect of electricity on solutions, coined term "electrolysis" as a splitting of molecules with electricity, developed laws of electrolysis. Faraday himself was not a proponent of atomism.

  • J. Plucker

    Built one of the first gas discharge tubes ("cathode ray tube").

  • Dmitri Mendeleev

    Arranged elements into 7 groups with similar properties. He discovered that the properties of elements "were periodic functions of the their atomic weights". This became known as the Periodic Law.

  • James Clerk Maxwell

    James Clerk Maxwell Proposed electric and magnetic fields filled the void.

  • Sir William Crookes

    Discovered cathode rays had the following properties: travel in straight lines from the cathode; cause glass to fluoresce; impart a negative charge to objects they strike; are deflected by electric fields and magnets to suggest a negative charge; cause pinwheels in their path to spin indicating they have mass.