Atomic Structure

Atomic Structure

1. Energy levels

   • Electrons found in energy levels around nucleus
     • Numbered 1,2,3,4
       • Closer together as you move further
     • Subdivided into sublevels that contain orbitals
       • S, p, d or f
         • Orbital
           • Region where an electron is most likely to be found
             • Hold max. 2 electrons
           • Electrons fill lower energy orbitals first
         • S has 1 orbital
           • P has 3
             • Holds maximum 6 electrons
           • D has 5
             • Holds maximum 10 electrons
           • F has 7
             • Holds maximum 14 electrkns
           • Hold max 2 electrons
   • Why does 4s fill before 3D?
     • Energy levels start to overlap as they get further away from the nucleus and so 4s is of lower energy than 3D and fills first as lower energy always fills first