01Classification

The 7 periods of the periodic table

From period 1 (hydrogen, helium) to period 7 (superheavy elements). Element counts, filling subshells and properties by period.

1
Period 12 elements
Subshells1s
2
Period 28 elements
Subshells2s, 2p
3
Period 38 elements
Subshells3s, 3p
4
Period 418 elements
Subshells4s, 3d, 4p
5
Period 518 elements
Subshells5s, 4d, 5p
6
Period 632 elements
Subshells6s, 4f, 5d, 6p
7
Period 732 elements
Subshells7s, 5f, 6d, 7p