Atomic Timeline

By Apribadi
  • 442

    Democritus Theory

    Greek philospher Democritus (with his teacher) composed the theory that all matter was composed of indivisible elements

  • John Dalton and Atoms

    John Dalton develops a theory stating that all matter is composed of atoms of different weights. He had also propsed that atoms are spherical and in motion

  • Cathode Ray Tubes Created

    Sir William Crookes constructed a primitive cathode ray tube

  • Xrays Developed

    Wilhelm Rontgen discovered that certain chemicals glowed when exposed to cathode rays.

  • Radiation, energy, and the atom

    Pierre and Marie Curie theorized that radioactive particles cause atoms to break down, then releasing radiation that takes the form of energy and subatomic particles.

  • Electrons Discovered

    Electrons get discovered, using properties of cathode rays

  • Einstein and the nature of light

    Einstein creates theories on relativity and hypothosizes about the particle nature of light.
  • Period: to

    Charge of an electron measured

    Robert Millikan measured the charge of a single electron, known as the elementary charge.
  • Period: to

    Structure of Atom Developed

    Ernest Rutherford known as the father of nuclear physics, developed the theory for the structure of the atom.

  • Bohr improves the atomic model

    Neils Bohr developed the Bohr atomic model, with electrons travelling in orbits around the nucleus, and chemical properties being determined by how many electrons are in the outer orbits.

  • Math describes electron changes

    Erwin Shrodinger described how electrons move in wave form

  • The neutron is discovered

    James Chadwick discovers the neutron component of the atomic nucleus, explaining the nuclear fission of uranium 235.