atom timeline

  • 322

    beliefe of elements

    Aristotle taught this
  • 370

    discovery of atom

    Democritus discovered​ the atom in 370bc
  • discovery of the role oxygen plays in combustion.

    Antonie Lavosier discovery of the role oxygen plays in combustion. He recognized and named oxygen (1778) and hydrogen (1783) and opposed the phlogiston theory. Lavoisier helped construct the metric system, wrote the first extensive list of elements, and helped to reform chemical nomenclature.
  • discovery of the law of constant composition

    Joseph Proust discovered the law of constant composition
  • daltons atomic theory everything made of atoms

    John Dalton had this idea
  • electron discovered

    J.J. Thomson discovered the electron.
  • discovery of two new elements, radium and polonium.

    Madame Curie discovered two new elements, radium and polonium.
  • Albert einstein created the theory of relativity

    Albert einstein created the theory of relativity, which laid the basis for the release of atomic energy
  • found the nucleas

    Ernest Rutherford found a massive positively charged center of the atom
  • theory for the hydrogen atom based on quantum theory was made

    Niels Bohr proposed a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well-defined quantities.
  • development of Moseley's law in X-ray spectra

    Henry Moseley justification from physical laws of the previous empirical and chemical concept of the atomic number. This stemmed from his development of Moseley's law in X-ray spectra
  • the quantum theory of energy originated

    Max Planck best known as the originator of the quantum theory of energy
  • William Crookes helped devolope atomic physics

  • understanding of the structure of the atom

    Robert Millikan's oil drop experiment helped to quantify the charge of an electron, which contributed greatly to our understanding of the structure of the atom and atomic theory.
  • quantum mechanics included in atomic study.

    Werner Heisenberg contributed to the atomic theory by including quantum mechanics,
  • ways to find the likelihood of finding an electron in a certain position.

    Erwin Schrodinger used mathematical equations to describe the likelihood of finding an electron in a certain position.
  • started predicting the wave nature of electrons.

    Louis deBroglie best known for his research on quantum theory and for predicting the wave nature of electrons.
  • neutron discovered

    James Chadwick interpreted this radiation as being composed of particles with a neutral electrical charge and the approximate mass of a proton. This particle became known as the neutron.