Periodic table block
s-block elements
The s-block collects the elements whose outermost electrons occupy an s subshell: hydrogen and helium plus the alkali metals of group 1 and the alkaline earth metals of group 2. An s subshell holds at most two electrons, so the block is only two groups wide, and its metals are among the most reactive known.
At a glance
- Elements
- 14
- Atomic numbers
- 1 to 88
- Block
- s-block
- Periods
- 1, 2, 3, 4, 5, 6, 7
- Phase at STP
- solid (11), gas (2)
Shared properties
- Outermost electrons in an s subshell, which holds at most two electrons
- Contains groups 1 and 2 plus hydrogen and helium
- Its metals readily lose one or two electrons, giving +1 and +2 ions
- Includes some of the most reactive metals in the periodic table