Lithium is a Group 1 (IA) element containing just a single valence electron (1s22s1). Group 1 elements are called "alkali metals". Lithium is a solid only about half as dense as water. A freshly cut chunk of lithium is silvery, but tarnishes in a minute or so in air to give a grey surface.
Lithium is mixed (alloyed) with aluminium and magnesium for light-weight alloys, and is also used in batteries, some greases, some glasses, and in medicine.
- Name: lithium
- Symbol: Li
- Atomic number: 3
- Atomic weight: [ 6.941 (2)] g m r
- CAS Registry ID: 7439-93-2
- Group number: 1
- Group name: Alkali metal
- Period number: 2
- Block: s-block
- Standard state: solid at 298 K
- Colour: silvery white/grey
- Classification: Metallic
