Symbol	Sc
Atomic number	21
Group	3 (Scandium group)
Period	4
Block	d
Classification	Transition Metal

Appearance	Silvery white
Color	Silver

Number of protons	21 p+
Number of neutrons	24 n0
Number of electrons	21 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.

Phase at STP	Solid
Density	2.985 g/cm3
Atomic weight	44.9559 u

Melting point	1814 K 1540.85 °C 2805.53 °F
Boiling point	3109 K 2835.85 °C 5136.53 °F
Heat of vaporization	304.8 kJ/mol

Electronegativity (Pauling Scale)	1.36
Electron affinity	18 kJ/mol
Oxidation states	0, +1, +2, +3 (an amphoteric oxide)
Ionization energies	633.1 kJ/mol 1235 kJ/mol 2388.6 kJ/mol 7090.6 kJ/mol 8843 kJ/mol 10679 kJ/mol 13310 kJ/mol 15250 kJ/mol 17370 kJ/mol 21726 kJ/mol 24102 kJ/mol 66320 kJ/mol 73010 kJ/mol 80160 kJ/mol 89490 kJ/mol 97400 kJ/mol 105600 kJ/mol 117000 kJ/mol 124270 kJ/mol 547530 kJ/mol 582163 kJ/mol

Electron configuration Shorthand configuration	[Ar] 3d1 4s2
Electron configuration Full configuration	1s2 2s2 2p6 3s2 3p6 3d1 4s2
Electron configuration chart	1s2 2s2 2p6 3s2 3p6 3d1 4s2
Electrons per shell	2, 8, 9, 2
Valence electrons	3
Valency electrons	3
Bohr model	Figure: Shell diagram of Scandium (Sc) atom.
Orbital Diagram	1s 2s 2p 3s 3p 3d 4s

Prediction	Dmitrij Mendelejev (1871)
Discovery and first isolation	Lars 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.

CAS Number	7440-20-2
ChemSpider ID	22392
EC number	231-129-2
PubChem CID Number	23952