History of the Atom Timeline by Gabby and Lauren

By gabbyd103
  • 340

    Aristotle(340 BC)

    Aristotle(340 BC)
    Believed in the four elements air, earth, water, and fire and that all these forms were of smaller matter
    Aristotle used observations from other scientists
    His description was a circle with a nucleus and electron "History of Atoms." History of Atoms. N.p., n.d. Web. 19 Feb. 2014.
  • 400

    Democritus(400BC)

    Democritus(400BC)
    First person to come up with the idea that things are made up of smaller invisible parts; made up of substances
    He used theories from observations
    Democrituss' description of his discovery was a round sphere. "Atomic Structure Timeline." Atomic Structure Timeline. N.p., n.d. Web. 19 Feb. 2014.

  • Dalton

    Dalton
    Dalton discovered that matter is composed of tiny particles called atoms and all atoms of the one element are identical but are different from the atoms of other elements.
    Dalton used the Law of Mass Conservation, Law of Constant Compostition, and Law of Multiple Proporties.
    He thought the atom looked like a sphere "History of Atoms." History of Atoms. N.p., n.d. Web. 19 Feb. 2014.

  • Thomas

    Thomas
    -Thomas believed that atoms consists of a large sphere of uniform positive charge embedded with negatively charged particles. -He used the "Plum Pudding" method
    "Atomic Structure Timeline." Atomic Structure Timeline. N.p., n.d. Web. 19 Feb. 2014.

  • Rutherford

    Rutherford
    -Rutherford discoved that atoms are very small positively charge nucleus that is mostly made up of mass. It has a large volume around the nucleus, and the number of protons equals the number of electrons
    -He used the Gold Foil Experiment
    -He thought it looked like a planitary model
    "History of Atoms." History of Atoms. N.p., n.d. Web. 19 Feb. 2014.

  • Bohr

    Bohr
    -Bohr discovered that protons in the nucleus electrons surrounded electrons and move in certain paths. Elements determine the electron chemical property.
    - Bohr used Rutherford theory to establish his own
    -Bohr thought that the first shell had two electron, the second shell had 8 electrons, and the third shell had eighteen electrons with a nucleus.
    "History of Atoms." History of Atoms. N.p., n.d. Web. 19 Feb. 2014.

  • Heisenberg and Shrodinger

    Heisenberg and Shrodinger
    -Discovered that electrons are waves
    -He used the "Two-Split Experiement"
    -He thought that there was a electron cloud surrounding the nucleus
    "HISTORY OF THE ATOM FROM DEMOCRITUS TO BOHR AND SCHRÖDINGER." HISTORY OF THE ATOM FROM DEMOCRITUS TO BOHR AND SCHRÖDINGER. N.p., n.d. Web. 21 Feb. 2014.