The Atomic Timeline

By Zac2617
  • The Alchemists
    500 BCE

    The Alchemists

    Broke down the chemical composition into 4 basic elements, fire, water, earth, and wind. This laid the foundation of the periodic table.
  • Period: 500 BCE to

    Years Where Discoveries Were Made

  • Plato
    427 BCE

    Plato

    Discovered that atoms of matter must derive from the 5 fundamental solids (he was wrong)
  • Democritus
    400 BCE

    Democritus

    Discovered atoms were the basic building blocks of matter
  • Robert Boyle

    Robert Boyle

    He discovered boyle's law, which is that the volume of a gas increases as the pressure decreases
  • Antone Lavoisier

    Antone Lavoisier

    Discovered that oxygen is essential to combustion and the law of conservation of mass.
  • Billiard ball model

    Billiard ball model

    Used wooden balls to represent solid, sphere shaped particles
  • John Dalton

    John Dalton

    He discovered that all matter is composed of atoms
  • Amedeo Avogadro

    Amedeo Avogadro

    Founded a hypothesis that equal volumes of different gases contain an equal number of molecules if the temperature and pressure are the same
  • Dmitri Mendeleev

    Dmitri Mendeleev

    Made symbols for the chemical elements in order based off of their atomic weight
  • Ernest Rutherford

    Ernest Rutherford

    First person to split the atom
  • Pierre and Marie Curie

    Pierre and Marie Curie

    Discovered radioactive pollution and radium in uranium
  • JJ Thompson

    JJ Thompson

    Discovered that all atoms are composed of electrons
  • Plum pudding model

    Plum pudding model

    Showed that electrons are embedded in a shape of positively charged electrons
  • Albert Einstein

    Albert Einstein

    He mathematically proved that atoms exist
  • Robert Millikan

    Robert Millikan

    Discovered that theres a fundamental electric charge known as the electrons charge
  • Solar system model

    Solar system model

    It was a planetary model that mirrors the solar system and showed how electrons have a circular orbit similar to it around the nucleus
  • Neils Bohr

    Neils Bohr

    Discovered that electrons move around the nucleus, but only in prescribed orbits and if electrons jump to a lower energy orbit the difference is sent out as radiation.
  • Henry G J Mosely

    Henry G J Mosely

    Found that the atomic number is the amount of positive charges in the nucleus
  • Werner Heisenburg

    Werner Heisenburg

    Discovered the uncertainty principle (particles position and momentum cannot be exactly known)
  • Erwin Schrodinger

    Erwin Schrodinger

    Created an equation for the distribution of electron in an atom
  • Electron cloud model

    Electron cloud model

    It had a dense nucleus covered by electrons on different levels in orbit
  • James Chadwick

    James Chadwick

    Proved that neutrons exist and that particles devoid any electrical charge