Developing Atomic Theory

By kupperdupper
  • 400 BCE

    Democritus

    Democritus theorized about matter being made of tiny particles
  • 340 BCE

    Aristotle

    Aristotle thought that all matter was made of 4 basic elements
  • 500

    Alchemists

    Alchemists theorized that all metals were made of sulfur and mercury
  • 1492

    Columbus landed in america

  • Robert Boyle

    Robert Boyle thought the elements could not be split into smaller forms

  • American Revolution start

  • American Revolution end

  • John Dalton

    John Dalton thought that atoms were indestructible building blocks of matter

  • Dmitri Mendeleev

    Dmitri Mendeleev made the first periodic table

  • J. J. Thompson

    J. J. Thompson discovered the first electron

  • Robert Millikan

    Robert Millikan helped to quantify the charge of the electron

  • Ernest Rutherford

    Rutherford found that the atom is mostly empty space

  • Hans Geiger

    He invented the Geiger counter with measures radiation. He also helped with the gold foil experiment, which showed the atomic nucleus.

  • Neils Bohr

    He created the Bohr model, which showed that electrons could have stable orbits around their nucleus

  • World War 1 Start

  • World War 1 End

  • World War 2 Start

  • World War 2 End

  • Hiroshima