Element category
Alkali metals
The alkali metals are the metals of group 1, running from lithium down to francium. Each atom carries a single electron in its outermost s subshell, and losing that electron to form a +1 ion dominates the group's chemistry. Hydrogen also sits in group 1 but is a reactive nonmetal, not an alkali metal.
At a glance
- Elements
- 6
- Atomic numbers
- 3 to 87
- Block
- s-block
- Periods
- 2, 3, 4, 5, 6, 7
- Phase at STP
- solid (5)
Shared properties
- Soft, silvery metals with low densities and low melting points for metals
- One valence electron, so compounds almost always contain the +1 ion
- React vigorously with water, releasing hydrogen gas and forming alkaline hydroxides
- Reactivity increases down the group as the outer electron sits farther from the nucleus