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Scandium (Sc)

Scandium is a chemical element of the periodic table with chemical symbol Sc and atomic number 21 with an atomic weight of 44.9559 u and is classed as transition metal and is part of group 3 (scandium group). Scandium is solid at room temperature.

Scandium in the periodic table

Atomic number21
Group3 (Scandium group)
ClassificationTransition Metal
AppearanceSilvery white
Color Silver
Number of protons21 p+
Number of neutrons24 n0
Number of electrons21 e-
From Wikipedia, the free encyclopediaScandium 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.

Physical properties

Phase at STPSolid
Density2.985 g/cm3
Atomic weight44.9559 u

Thermal properties

Melting point1814 K
1540.85 °C
2805.53 °F
Boiling point3109 K
2835.85 °C
5136.53 °F
Heat of vaporization304.8 kJ/mol

Atomic properties

Electronegativity (Pauling Scale)1.36
Electron affinity18 kJ/mol
Oxidation states0, +1, +2, +3
(an amphoteric oxide)
Ionization energies
  1. 633.1 kJ/mol
  2. 1235 kJ/mol
  3. 2388.6 kJ/mol
  4. 7090.6 kJ/mol
  5. 8843 kJ/mol
  6. 10679 kJ/mol
  7. 13310 kJ/mol
  8. 15250 kJ/mol
  9. 17370 kJ/mol
  10. 21726 kJ/mol
  11. 24102 kJ/mol
  12. 66320 kJ/mol
  13. 73010 kJ/mol
  14. 80160 kJ/mol
  15. 89490 kJ/mol
  16. 97400 kJ/mol
  17. 105600 kJ/mol
  18. 117000 kJ/mol
  19. 124270 kJ/mol
  20. 547530 kJ/mol
  21. 582163 kJ/mol

Electron configuration for scandium

Electron configuration
Shorthand configuration
[Ar] 3d1 4s2
Electron configuration
Full configuration
1s2 2s2 2p6 3s2 3p6 3d1 4s2
Electron configuration chart
Electrons per shell2, 8, 9, 2
Valence electrons 3
Valency electrons 3
Bohr model
ScandiumElectron shell for Scandium, created by Injosoft ABSc
Figure: Shell diagram of Scandium (Sc) atom.
Orbital Diagram

The history of Scandium

PredictionDmitrij Mendelejev (1871)
Discovery and first isolationLars Fredrik Nilson (1879)
Discovery of scandium
Dmitri Mendeleev, who is referred to as the father of the periodic table, predicted the existence of an element ekaboron, with an atomic mass between 40 and 48 in 1869. Lars Fredrik Nilson and his team detected this element in the minerals euxenite and gadolinite in 1879. Nilson prepared 2 grams of scandium oxide of high purity. He named the element scandium, from the Latin Scandia meaning "Scandinavia". Nilson was apparently unaware of Mendeleev's prediction, but Per Teodor Cleve recognized the correspondence and notified Mendeleev. Metallic scandium was produced for the first time in 1937 by electrolysis of a eutectic mixture of potassium, lithium, and scandium chlorides, at 700–800 °C.


List of unique identifiers for Scandium in various chemical registry databases
CAS Number7440-20-2
ChemSpider ID22392
EC number231-129-2
PubChem CID Number23952