atomic theory

By paulc
  • 364


    Aristotle believed in the four elements of earth, wind, water, and fire. He also believed that a portion of matter could be cut in half infinitely many times. (364 B.C.)
  • 420


  • Antoine Lavoisier

    Antoine Lavoisier
    Antoine Lavoisier (1743-1794) is called the Father of Modern Chemistry, having discovered that water is made of hydrogen and oxygen. He also invented the analytical balance and showed that chemical elements were neither created nor destroyed, just combined into different compounds in chemical reactions. From this work follows one of the most fundamental principles of physics, the conservation of mass
  • Joseph Proust

    Joseph Proust
  • John Dalton

    John Dalton
  • J.J Thomson

    J.J Thomson
  • Robert Millikan

    Robert Millikan
    Millikan dtermined the unit charge of the electron. His discovery allowed for the calculation of the electron and all positively charged atoms.
  • Ernest Rutherford

    Ernest Rutherford
    Ernest Rutherford published an atomic theory in which the atom has a central positive nucleus surrounded by negative orbiting electrons.
  • Neils Bohr

    Neils Bohr
    Bohr applied the quantum theory to Rutherford's atomic structure and discovered a method of calculating the possible energy levels of stationary electrons. He also discovered that an emission of light occurs when an electron moves into a differnet energy level orbit.