Atom 1

The Amazing Evolution of the Atom

By lexiC
  • First Idea of Atoms
    460

    First Idea of Atoms

    In 460 B.C, a Greek philosopher named Democritus develops the idea of atoms. His idea is that if you break a piece of matter in half over and over again, it will eventually be so small that it cannot be broken in half again. He called this tiny piece of matter an atom.
  • Lavoisier's Discoveries

    Lavoisier's Discoveries

    Lavoisier created the formula for conservation of matter and discovered the difference between an element and a compound.
  • John Dalton

    John Dalton

    In the 1800's, nearly 2000 years after Democritus' idea, an English chemist named John Dalton did experiments with different chemicals that proved matter was made of lumpy particles.
  • First Model of the Atom

    First Model of the Atom

    In 1897, a physicist named J.J Thomson discovered the electron and created a model for the structure of the atom. He knew that electrons had a negative charge and thought that meant matter had a positive charge.
  • Max Planck

    Max Planck

    In 1900 Max Planck, a theoretical physicist, discovered that when you vibrate atoms hard enough you can measure the energy in units. He called the units "quanta."
  • Electron

    Electron

    In the year of 1908, Robert Millikan discovered the electric charge of the electron.
  • Ernest Rutherford

    Ernest Rutherford

    In 1909 an English guy named Ernest Rutherford discovered that all the mass of an atom was in a small, positive charged ball in its center.
  • The Bohr Atomic Model

    The Bohr Atomic Model

    A Danish man called Neils Bohr presents the Bohr atomic model.
  • The Elements

    The Elements

    Glen T. Seaborg identified elements heavier than Uranium and added elements 94 through 102