Scandium
Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic d-block element, it has historically been sometimes classified as a rare earth element, together with yttrium and the lanthanoids. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia.
A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.
18 is the [Ar] core total across three shells.
At a glance
- Atomic number
- 21
- Atomic mass
- 44.955909 u
- Phase
- Solid
- Density
- 2.985 g/cm³
- Melting point
- 1,814 K
- Boiling point
- 3,109 K
- First ionization energy
- 633.1 kJ/mol
- Electronegativity
- 1.36
- Electron affinity
- 18 kJ/mol
- Molar heat capacity
- 25.52 J/(mol·K)
- Period
- 4
- Appearance
- silvery white
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.