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The Periodic Table

Explore trends and properties of elements in Groups I, II, VII, and 0

Click a group or element to view details.

Groups →
Group I: Alkali Metals
Group II: Alkaline Earth Metals
Transition Metals
Group III
Group IV
Group V
Group VI
Group VII: Halogens
Group 0: Noble Gases
1
2
3
4
5
6
7

Select a group to explore

HKDSE Tip

  • Ordering of elements:
    Elements in the modern Periodic Table are arranged in order of increasing atomic number (the number of protons), not relative atomic mass.
  • The metal–non-metal boundary:
    Metalloids (such as Boron (B) and Silicon (Si)) lie along the zig-zag diagonal line separating metals (left) and non-metals (right) in the Periodic Table.
  • Groups vs. periods:
    Elements in the same group have the same number of outermost shell electrons and thus share similar chemical properties to achieve a stable octet (or duet) arrangement, whereas elements in the same period have the same number of occupied electron shells.
  • The grid layout:
    Remember that groups are vertical columns (elements share similar chemical properties), while periods are horizontal rows (elements share the same number of occupied electron shells).
  • The trend:
    Moving across a period (from left to right), melting and boiling points increase from Group I to IV (peaking at Group IV), then drop sharply from Group V onwards.