(L5) ARRANGEMENT OF ELEMENTS IN THE PERIODIC TABLE

• The significance of the period is that they give the energy levels of the electron
• period number gives the value of the energy level of the valence orbital of the atoms
• outermost orbital


  location of valence electron
• valence electron


  electrons occupying the highest occupied energy level
• Traditionally, United States, European 


  What is the 3 ways to label the groups in the PT?
• On 1985, the IUPAC proposed a new labeling system
• Group A1 is the Alkali metals
• Group A2 is the Alkaline earth metals
• Group A3 is the Earth Metals/Boron Group
• Group A4 is the Tetrels/Carbon Group 
• Group A5 is the Pnictogens/Nitrogen Group
• Group A6 is the Chalcogens/Oxygen group
• Group 7A is the Halogens 
• Group 8A is the Noble gases
• Group B is the Transition Metals
• Inner transition metals


  • metallic in nature
  • partially filled up f orbitals
  • lanthanide and actinide series