ATOMS

ATOMS

1. Atom Theory

   • 1.Democritus
     • atoms=indivisibles
     • discovers atoms
   • 2.John Dalton
     • 18th century
     • could be combinations of igual atoms
     • atoms can be arrenged in different maneers
   • 3.Rutherford
     • 1911
     • e´ orbited around a + charge
   • 4.Niels Bohr
     • 1913
     • discovers atomic model
       • atoms disosed in energy levels
     • atoms can move in the energy level without loosing energy
   • 5.Erwin Schroedinger
     • 1920
     • electrons can gain and lose energy moving between energy levels
     • the exact position of the electron depends on the observer

2. Structure of an Atom

   • smallest particles of matter
   • Size: 1-2.5 Å (=10-10m)
   • Mass
     • p+ =1amu
       • amu= atomic mass unit
     • e´=0.0005 amu
       • amu= atomic mass unit
     • n =1 amu
       • amu= atomic mass unit
   • Charges
     • p+ = +1
     • e´= -1
     • n = ø
   • most stable configuration
     • 2,0,0
     • 2,8,8
     • 2,0,8
     • 2,8,0