History of the atom

By gummythor
  • 430 BCE

    Democritus

    Democritus
    -Discovered the atom

  • Dalton

    Dalton
    -All matter is composed of atoms
    -Atoms are indivisible and indestructible

  • Thomson

    Thomson
    -Discovered the electron using a cathode ray tube
    -Proposed that atoms have negatively charged electrons embedded in a positively charged substance

  • Rutherford

    Rutherford
    -Performed the gold foil experiment
    -Discovered the nucleus
    -Discovered that the nucleus contains the protons and neutrons of an atom

  • Bohr

    Bohr
    -Made the Bohr model
    -Also called the planetary model because it depicts electrons orbiting around the nucleus of the atom

  • Modern Atomic Theory

    Modern Atomic Theory
    -Electron cloud model is the modern model of an atom
    -says we cannot know exactly where an electron is at any given time