Period 4
Period 4
Eighteen elements, the first appearance of the transition metals (Sc to Zn) with the 3d block.
Element count
18
First element
Z = 19
Last element
Z = 36
Period 4 introduces the d-block: the ten transition metals from scandium to zinc that give this row its richness (iron, copper, nickel, zinc) and its many filling exceptions (Cr, Cu). It ends with the p-block elements (Ga to Kr) — among them gallium, which melts in the hand.
Filling subshells
4s3d4p
18 elements
19K
Potassium
Alkali metals · Period 4
20Ca
Calcium
Alkaline earth metals · Period 4
21Sc
Scandium
Transition metals · Period 4
22Ti
Titane
Transition metals · Period 4
23V
Vanadium
Transition metals · Period 4
24Cr
Chrome
Transition metals · Period 4
25Mn
Manganèse
Transition metals · Period 4
26Fe
Fer
Transition metals · Period 4
27Co
Cobalt
Transition metals · Period 4
28Ni
Nickel
Transition metals · Period 4
29Cu
Cuivre
Transition metals · Period 4
30Zn
Zinc
Transition metals · Period 4
31Ga
Gallium
Post-transition metals · Period 4
32Ge
Germanium
Metalloids · Period 4
33As
Arsenic
Metalloids · Period 4
34Se
Sélénium
Reactive nonmetals · Period 4
35Br
Brome
Halogens · Period 4
36Kr
Krypton
Noble gases · Period 4