3.1 Periodic table

• Groups: Go vertically down
• Periods: horizontal rows of elements
  • There are 7 periods. The period number is equal to principle quantum number n of highest occupied energy level

• Periodic table is split roughly into metals, non-metals and metalloids
• Left of line is metals, right of line is nonmetals, touching line is metalloids.
  • Metals:
    • Good conductors
    • Malleable
    • Ductile
    • Have lustre
    • Lose electrons
  • Non-metals:
    • Poor conductors
    • Gain electrons
  • Metalloids
    • Close to the line, have both metallic and non-metallic properties
    • Some metalloids are semi-conductors

• The periodic table is split into four blocks based on s, p, d, f
• Occupancy of electrons for each sub-level is:

*Two electrons per each orbital

• Number of Valence electron (outer-shell electrons) can be found from the group number of the s and p block elements.