PERIODICITY

• Atomic Radius: the distance from the nucleus to the outer shell

  • moving top to bottom of the table the radius enlarges
  • moving across the left to right the table the radius decreases
• The greater the radius the less electron affinity
• Ionisation energy: the energy needed to make an ion

  e.g. Na - e- --> Na+

  • this requires energy that goes against the electrostatic force
• electron affinity/ electron negativity

  • negative electrons have a greater chance of occurring hence a greater electron affinity
  • electron affinity is spontaneous and doesn't need an extended source of energy
  • after grabbing electrons the atoms release extra energy
• F (fluorine) is the most reactive electron, has the most affinity
• the more electrons in the same shell the stronger the electrostatic attraction
• electrostatic attraction is stronger for smaller atoms
• the total electrostatic attraction doesn't change is only gets transferred

  
• periodicity:

  A) Atomic

  B) energy

  C) water

  D) metallic