What does «cobre» mean in Spanish?
- A metallic element known since prehistoric times for its valuable mechanical properties. Unalloyed, it has a characteristic reddish color and a lustrous metallic luster. It conducts electricity better than any other element except silver and is also a good conductor of heat. It is also distinguished by its great toughness, which makes it very useful in the form of wires and cables, and it is particularly ductile and malleable. Its regular hardness can be improved by alloying or by certain mechanical treatments such as rolling and beating. Its chemical symbol is Cu, its atomic number is 29 and its atomic weight 63.57. It has ten known isotopes, of which only two are stable: Cu 63 (29 protons and 34 neutrons) and Cu 65 (29 protons and 36 neutrons). It reaches its melting point at 1083 °C and its boiling point at 2325 °C. Finally, its density is 8.94 g/cm3. See Element.