Atomic model

By JoeCantella
  • 500 BCE

    The Alchemists

    The Alchemists
    Created the atomic theory. believed that everything was made up of atoms of differing weights that combine in simple ratios by weight.
  • 450 BCE

    Aristotle

    Aristotle
    Did not believe in atomic theory and taught against it. believed there were four elements. Water, fire, air, and earth.
  • 427 BCE

    Plato

    Plato
    Plato's theory of forms. believed that everything we see and know is made up of "forms".
  • 400 BCE

    Democritus

    Democritus
    found that everything is made of atoms. believed that all atoms are indestructible and are infinite amounts of them.

  • Robert Boyle

    Robert Boyle
    Developed a definition of an element. he also contributed to "the death" of the four elements,

  • Lavoiser

    Lavoiser
    Helped in discovering the law of conservation of mass. Found that the total mass of products and reactants is always the same.

  • John Dalton

    John Dalton
    Formulated the first modern description of the atom as a fundamental building block of chemical structures. Also developed the law of multiple proportions.

  • Dmitri Mendeleev

    Dmitri Mendeleev
    Created the periodic table. Organized elements in rows according to their atomic mass to create the periodic table.

  • J.J. Thomson

    J.J. Thomson
    Discovered the electron. Created the "plum pudding" model.

  • The Curies

    The Curies
    discovered radium and polonium. helped to learn about radioactivity.

  • Albert Einstein

    Albert Einstein
    Mathematically proved the existence of atoms which helped improve all science through use of statistics and probability.

  • Robert Millikan

    Robert Millikan
    used "the oil drop" experiment to help quantify the charge of an electrons. helped advance our knowledge of the structure of the atom and the atomic theory.

  • Ernest Rutherford

    Ernest Rutherford
    Found the atom is made up of mostly empty space with a nucleus packed with particles in the middle. Also discovered alpha and beta rays.

  • Neils Bohr

    Neils Bohr
    Created the Bohr model; explained how electrons orbit around a atomic nucleus.

  • Henry G. J. Mosely

    Henry G. J. Mosely
    Discovered the systematic relation between wave-length and atomic number. he named this Moseley's Law.

  • Werner Heisenberg

    Werner Heisenberg
    formed quantum theory in terms of matrices. He also discovered the uncertainty principle, which shows that particles position and momentum cannot both be known exactly