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Period 6
Period 6
The longest: 32 elements, including the 15 lanthanides squeezed into the f-block between Cs 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 15 lanthanides (La 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
55Cs
Caesium
Alkali metals · Period 6
56Ba
Barium
Alkaline earth metals · Period 6
57La
Lanthanum
Lanthanides · Period 6
58Ce
Cerium
Lanthanides · Period 6
59Pr
Praseodymium
Lanthanides · Period 6
60Nd
Neodymium
Lanthanides · Period 6
61Pm
Promethium
Lanthanides · Period 6
62Sm
Samarium
Lanthanides · Period 6
63Eu
Europium
Lanthanides · Period 6
64Gd
Gadolinium
Lanthanides · Period 6
65Tb
Terbium
Lanthanides · Period 6
66Dy
Dysprosium
Lanthanides · Period 6
67Ho
Holmium
Lanthanides · Period 6
68Er
Erbium
Lanthanides · Period 6
69Tm
Thulium
Lanthanides · Period 6
70Yb
Ytterbium
Lanthanides · Period 6
71Lu
Lutetium
Lanthanides · Period 6
72Hf
Hafnium
Transition metals · Period 6
73Ta
Tantalum
Transition metals · Period 6
74W
Tungsten
Transition metals · Period 6
75Re
Rhenium
Transition metals · Period 6
76Os
Osmium
Transition metals · Period 6
77Ir
Iridium
Transition metals · Period 6
78Pt
Platinum
Transition metals · Period 6
79Au
Gold
Transition metals · Period 6
80Hg
Mercury
Transition metals · Period 6
81Tl
Thallium
Post-transition metals · Period 6
82Pb
Lead
Post-transition metals · Period 6
83Bi
Bismuth
Post-transition metals · Period 6
84Po
Polonium
Post-transition metals · Period 6
85At
Astatine
Halogens · Period 6
86Rn
Radon
Noble gases · Period 6