Copper (Cu)
Element 29 · Transition metal · Solid at 25 °C · Group 11, Period 4
Copper has wired the electrical age: it is the standard conductor in wiring and motors. It is also one of the few metals with a natural color, and the base of bronze and brass.
On the periodic table, copper sits in group 11 — the coinage metals — in period 4. It is one of 38 elements classified as a transition metal, and at room temperature (25 °C) it is a solid.
Transition metals occupy the wide d-block in the middle of the table. As a family they are hard, dense, high-melting metals that conduct heat and electricity well. Their partly filled d-orbitals let many of them take several oxidation states, form vividly colored compounds, and act as catalysts — which is why so much of industry, and so much of biology, runs on this block.
Properties of copper
| Atomic number (Z) | 29 |
|---|---|
| Symbol | Cu |
| Atomic mass | 63.546 |
| Category | Transition metal |
| Group | 11 |
| Period | 4 |
| Block | d-block |
| Metal / nonmetal | Metal |
| State at 25 °C | Solid |
| Electron configuration | [Ar] 3d10 4s1 |
| Electronegativity (Pauling) | 1.9 |
| Melting point | 1,084.62 °C (1,357.77 K / 1,984.32 °F) |
| Boiling point | 2,562 °C (2,835.15 K / 4,643.6 °F) |
| Density | 8.96 g/cm³ |
Position in the periodic table
Copper shares group 11 — the coinage metals with Silver (Ag), Gold (Au), Roentgenium (Rg). Elements in the same group have the same number of outer electrons, so they tend to behave alike chemically — comparing them is one of the fastest ways to see periodic trends in action.
Physical properties
Copper melts at 1,084.62 °C (1,357.77 K / 1,984.32 °F) and boils at 2,562 °C (2,835.15 K / 4,643.6 °F), giving it a liquid range of about 1,477.4 °C at standard pressure.
Its density is 8.96 g/cm³.
See also: the interactive periodic table, how to read the periodic table, periodic trends.