Period 1 element
A period 1 element is one of the chemical elements in the first row (or period) of the periodic table of the elements.
These are:
| Group | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| # Name | 1 H |
2 He | ||||||||||||||||
| e--conf | ||||||||||||||||||
| Alkali metals | Alkaline earths | Lanthanide | Actinides | Transition metals |
| Poor metals | Metalloids | Nonmetals | Halogens | Noble gases |