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Alkali metals

Lithium

A soft, light metal central to rechargeable batteries.

Atomic #3Mass6.94Blocks-blockPeriod2Group1
Li3 · 6.94
3D Atom Explorer

Inside the Lithium atom

Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Lithium atom step by step.

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Electron configuration

[He] 2s1

A neutral Lithium atom has 3 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.

Shell distribution

Shell 12 e⁻Shell 21 e⁻

Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.

Properties

Physical & atomic properties

State (room temp)
Solid
Melting point
454 K (181 °C)
Boiling point
1603 K (1330 °C)
Density
0.534 g/cm³
Electronegativity
0.98 Pauling
Atomic radius
145 pm
1st ionization energy
520 kJ/mol
Category
Alkali metals
History

Discovery & naming

Discovered
1817
Discovered by
Johan August Arfwedson
Origin of name
Greek 'lithos', meaning stone.

Notable uses

Rechargeable batteries, aircraft alloys, and mood-stabilizing medicines.

Cosmic origin

Where Lithium comes from

Several comparable sources

A trace was made in the Big Bang. The rest is linked to cosmic ray spallation and to some dying stars and novae.

Simplified origin map — many elements form through more than one astrophysical pathway.

Summary

Atomic number
3
Atomic mass
6.94
Category
Alkali metals
Group · Period
1 · 2
Block
s-block
Shells
2 · 1