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Copper (Cu)

Copper is a chemical element of the periodic table with chemical symbol Cu and atomic number 29 with an atomic weight of 63.5463 u and is classed as transition metal and is part of group 11 (coinage metals). Copper is solid at room temperature.

Copper in the periodic table

Atomic number29
Group11 (Coinage metals)
ClassificationTransition Metal
AppearanceRed-orange metallic luster
Color Copper
Number of protons29 p+
Number of neutrons35 n0
Number of electrons29 e-
From Wikipedia, the free encyclopediaCopper 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.

Physical properties

Phase at STPSolid
Density8.96 g/cm3
Atomic weight63.5463 u

Thermal properties

Melting point1357.77 K
1084.62 °C
1984.316 °F
Boiling point2835 K
2561.85 °C
4643.33 °F
Heat of vaporization300.5 kJ/mol

Atomic properties

Electronegativity (Pauling Scale)1.9
Electron affinity119.235 kJ/mol
Oxidation states−2, 0, +1, +2, +3, +4
(a mildly basic oxide)
Ionization energies
  1. 745.5 kJ/mol
  2. 1957.9 kJ/mol
  3. 3555 kJ/mol
  4. 5536 kJ/mol
  5. 7700 kJ/mol
  6. 9900 kJ/mol
  7. 13400 kJ/mol
  8. 16000 kJ/mol
  9. 19200 kJ/mol
  10. 22400 kJ/mol
  11. 25600 kJ/mol
  12. 35600 kJ/mol
  13. 38700 kJ/mol
  14. 42000 kJ/mol
  15. 46700 kJ/mol
  16. 50200 kJ/mol
  17. 53700 kJ/mol
  18. 61100 kJ/mol
  19. 64702 kJ/mol
  20. 163700 kJ/mol
  21. 174100 kJ/mol
  22. 184900 kJ/mol
  23. 198800 kJ/mol
  24. 210500 kJ/mol
  25. 222700 kJ/mol
  26. 239100 kJ/mol
  27. 249660 kJ/mol
  28. 1067358 kJ/mol
  29. 1116105 kJ/mol

Electron configuration for copper

Electron configuration
Shorthand configuration
[Ar] 3d10 4s1
Electron configuration
Full configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s1
Electron configuration chart
Electrons per shell2, 8, 18, 1
Valence electrons 1
Valency electrons 1,2
Bohr model
CopperElectron shell for Copper, created by Injosoft ABCu
Figure: Shell diagram of Copper (Cu) atom.
Orbital Diagram

The history of Copper

DiscoveryMiddle East (9000 BC)
Discovery of copper
Copper was probably the first metal mined and crafted by humans. It was originally obtained as a native metal and later from the smelting of ores. Earliest estimates of the discovery of copper suggest around 9000 BC in the Middle East. It was one of the most important materials to humans throughout the Chalcolithic and Bronze Ages. Copper beads dating from 6000 BC have been found in Çatal Höyük, Anatolia and the archaeological site of Belovode on the Rudnik mountain in Serbia contains the world's oldest securely dated evidence of copper smelting from 5000 BC.


List of unique identifiers for Copper in various chemical registry databases
CAS Number7440-50-8
ChemSpider ID22414
EC number231-159-6
PubChem CID Number23978