History of Atomic Theory

By kaitlynwalker
  • 460

    Democritus

    Democritus
    Discovered the atom.

  • John Dalton

    John Dalton
    Believed-
    1. Atoms are indivisable and indestructible.
    2.All atoms are of a given element are idential in mass and properties
    3.Compunds are formed by a combination of two or more different kinds of atoms.
    4. A chemical reaction is a rearrangement of atoms.
    5.Atoms can be neither created nor destroyed. He claimed that atoms look like spheres, with each elemont having its own size.

  • Neils Bohr

    Neils Bohr
    Proposed that electrons-
    1. Orbit the nucleus without losing energy.
    2. could only move in a fixed orbit of specific energies.

  • James Chadwick

    James Chadwick
    Discovered the neutron.

  • J.J. Thomson

    Won the Nobel prize in Physics.

  • Ernest Rutherford

    Ernest Rutherford
    Found out that Thomson's model of the atom was incorrect. Discovered the proton.