History of Atomic Theory

By spiritwalker

  • Theory made about matter is composed of tiny particles

    Leucippis and Democritis came up with the idea that matter is composed of tiny particles. This helped us understand the structure of an atom

  • The law of Conservation Of Mass is created

    Antione Lavoiser created Law of Conservation of Mass that states Even if matter changes shape or form its mass stays the same. He created this law in 1774. This law gave us more undersating about how matter works.

  • The Discovery of Electrons

    Joseph John Thompson discovers cathode rays aren't really waves, but very small negatively charged particles. This discovery gives us more information about how atoms are structured. Found in 1897.

  • Discovery of Nucleus

    In 1909, Earnest Rutherford did an experiment that resulted in him finding out that atoms have one, small concentrated part within them. It is know today as the nucleus. With this discovery we were able to learn more about the atom.

  • Bohr makes Bohr Diagram

    In 1911, Niels Bohr studied JJ's experiment. By calculating outcomes of his experiment, he was able to make the Bohr Diagram, which can show how many electrons surround an element.

  • Bohr's belief about electrons disproved.

    Werner Heisenberg disproves Bohr's belief about how electrons move in a neat, straight line, saying that it is impossible to actually calculate where they are. Him disproving Bohr's theory led to a quantum theory that is much more accurate. Created in 1900.