Period 6

Period 6

The longest: 32 elements, including the 14 lanthanides squeezed into the f-block between La and Hf.

Element count
32
First element
Z = 55
Last element
Z = 86

Period 6 is the first to bring in the f-block: the 14 lanthanides (Ce to Lu) sit inside the period and are detached visually at the bottom of the table to preserve readability. It contains precious metals (Pt, Au), mercury (liquid at room temperature) and the common stable heavy elements (Pb, Bi).

Filling subshells
6s4f5d6p

32 elements