29CuCopper63.5463[Ar] 3d¹⁰ 4s¹
transition metal

Copper

Copper is a chemical element with symbol Cu (from Latin:cuprum) and atomic number 29. It is a soft, malleable and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a reddish-orange color.

Electronic structure

A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.

Electrons by shell
Electron configuration
3d10
4s1

18 is the [Ar] core total across three shells.

Properties

At a glance

Atomic number
29
Atomic mass
63.5463 u
Phase
Solid
Density
8.96 g/cm³
Melting point
1,357.77 K
Boiling point
2,835 K
First ionization energy
745.5 kJ/mol
Electronegativity
1.9
Electron affinity
119.235 kJ/mol
Molar heat capacity
24.44 J/(mol·K)
Period
4
Appearance
red-orange metallic luster

Conditions and isotopes affect measured properties. Some properties of short-lived elements are predicted. Electronegativity uses the Pauling scale.

Keep exploring

Explore the stories, imagery, and reference data in more depth. Properties with no value in the reference are marked unavailable.