Copper (Cu)
Copper is the 29th element, a transition metal in the d-block. Its standard atomic weight is 63.546.
Copper
63.546
What the table records
- Atomic number
- 29
- Standard atomic weight
- 63.546
- Group
- 11
- Period
- 4
- Block
- d-block
- Category
- Transition metal
- [Ar] 3d10 4s1
- Valence electrons
- 11
- Typical valence
- Van der Waals radius
- 2 Å
- Covalent radius
- 1.32 Å
Molecules containing copper
The lightest named structures in this library that contain Cu.
Copper
Cu · 63.55 g/mol
Copper(1+)
Cu+ · 63.55 g/mol
Cupric cation
Cu+2 · 63.55 g/mol
COPPER(I) CHLORIDE
ClCu · 99 g/mol
Copper(I) acetate
C₂H₃CuO₂ · 122.59 g/mol
Cupric Chloride
Cl₂Cu · 134.45 g/mol
COPPER(I) OXIDE
Cu₂O · 143.09 g/mol
COPPER(I) BROMIDE
BrCu · 143.45 g/mol
Thiophenol copper(I) salt
C₆H₅CuS · 172.72 g/mol
Cupric acetate
C₄H₆CuO₄ · 181.63 g/mol
Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)
CuI · 190.45 g/mol
Bromo(thiobis(methane))copper
C₂H₆BrCuS · 205.59 g/mol
How to read these numbers
The standard atomic weight is an average over the isotopes as they occur naturally, which is why it is rarely a whole number. It is the figure a molar mass calculation uses. Work in mass spectrometry wants the monoisotopic mass of a single isotope instead, which is a different number.
The two radii are not the same measurement. The covalent radius is half the distance between two bonded atoms of the element; the van der Waals radius is how close a non-bonded atom gets before repulsion takes over, and is always the larger. Space-filling models are drawn with the second, ball-and-stick models with the first — which is why the same molecule looks so different in the two.