21Sc44.956
Transition Metald-block
Scandium
Element 21 on the periodic table, symbol Sc, group 3, period 4.
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.
Appearance: silvery white
Properties
- Atomic Number
- 21
- Atomic Mass
- 44.9559 u
- Group
- 3
- Period
- 4
- Block
- d-block
- Category
- Transition Metal
- State at 25 °C
- Solid
- Melting Point
- 1,814 K · 1,540.9 °C
- Boiling Point
- 3,109 K · 2,835.9 °C
- Density
- 2.985 g/cm³
- Atomic Radius
- 160 pm
- Electronegativity
- 1.36
- Oxidation States
- +3
- Abundance in Crust
- 22 mg/kg
- Discovered
- 1879
- Discovered By
- Lars Fredrik Nilson
Electron Configuration
[Ar] 3d1 4s2
1s2 2s2 2p6 3s2 3p6 4s2 3d1
Ionisation Energies (kJ/mol)
- 1. 633.1
- 2. 1,235
- 3. 2,388.6
- 4. 7,090.6
- 5. 8,843
- 6. 10,679
- 7. 13,310
- 8. 15,250
Elements near Scandium
Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.