Periodicity

• Periodicity: Repeating patterns or trends of physical or chemical properties
• The Periodic Table is split by highest energy orbital
• Atomic Radius and Periodicity

  • Outer electrons in same shell
  • More protons in nucleus
  • Same amount of shielding
  • Strong attraction between outer shell electrons and nucleus
  • Outer shell electrons pulled closer to nucleus
• First IE Energy and Periodicity

  • More protons
  • Atoms get smaller
  • Stronger attraction from nucleus to electron in outer shell
• Group 2 -> 3 First IE Energy

  • Group 2 is s orbital
  • Group 3 is p orbital
  • p orbital is higher energy than s orbital so easier to lose an electron
• Group 5 -> 6 First IE Energy

  • Group 6 loses electron from orbital from 2 electrons (p4)
  • Group 5 loses electron from orbital with 1 electron (p3)
  • Extra electron-electron repulsion make it easier to lose electrons from p4 than p3
• Electronegativity: Power of an atom to attract the 2 electrons in a covalent bond
• Electronegativity Periodicity:

  • More protons in nucleus
  • Smaller atomic radius
  • Stronger attraction between nucleus and 2 electrons in covalent bond
• Melting and Boiling Point Periodicity

  • Metallic bonds have strong attractions between metal and non-metal ions and delocalised electrons
  • Giant Covalent bonds have to break many strong covalent bonds
  • Simple molecular have weak van der Waals forces (bigger electrons have more van der Waals forces)
• Monatomic bonds have very weak van der Waals forces