Scandium is the 21st element of the periodic table. These scandium facts contain chemical and physical data along with general information and history.
Basic Scandium Facts
Name: Scandium
Atomic Number: 21
Element Symbol: Sc
Group: 3
Period: 4
Block: d
Element Family: Transition Metal
Atomic Mass: 44.955 908(5)
Electron Configuration: [Ar]3d14s2
Full: 1s22s22p63s23p63d14s2 (full)
Discovery: Lars Frederik Nilson in 1879
Mendeleev predicted the existence of an element between calcium and titanium because there was a gap in the atomic weights. Many chemists began searching for this element, but Swedish chemist Lars Nilson extracted scandium from a sample of the mineral euxenite. He extracted an oxide of ytterbium and an unknown element with an atomic weight of about 44. This placed the element in the position on the periodic table belonging to be Mendeleev’s missing element.
Name Origin: Scandium gets its name from the Latin Scandia which was the name for Scandinavia.
Isotopes:
Natural scandium is comprised of only one stable isotope 45Sc. Twenty three radioactive isotopes exist ranging from 37Sc to 60Sc.
45Sc
Scandium-45 is a stable isotope containing 24 neutrons. 100% of natural scandium is scandium-45.
Physical Data
Density: 2.99 g/cm3
Melting Point: 1814 K (1541 °C, 2806 °F)
Boiling Point: 3109 K (2836 °C, 5136 °F)
State at 20ºC: Solid
Heat of Fusion: 14.1 kJ/mol
Heat of Vaporization: 332.7 kJ/mol
Molar Heat Capacity: 25.52 J/mol·K
Atomic Data
Atomic Radius: 1.62 Å (empirical)
Covalent Radius: 1.70 Å
Van der Waals Radius: 2.11 Å
Electron Affinity: 18.139 kJ/mol
Electronegativity: 1.36
1st Ionization Energy: 633.088 kJ/mol
2nd Ionization Energy: 1234.99 kJ/mol
3rd Ionization Energy: 2388.655 kJ/mol
4th Ionization Energy: 7090.65 kJ/mol
5th Ionization Energy: 8842.88 kJ/mol
6th Ionization Energy: 10679 kJ/mol
7th Ionization Energy: 13315 kJ/mol
8th Ionization Energy: 15254.3 kJ/mol
Oxidation States: +3 (common), +2, +1 (uncommon)

Fun Scandium Facts
- Scandium is a silvery-white relatively light and soft metal at room temperature. When exposed to air, pure scandium develops a pink-yellow oxidation layer.
- Scandium is used in alloys much like aluminum. Scandium has a higher melting point than aluminum while having nearly the same density.
- Scandium is considered a rare-earth element because it is often found in rare-earth ores. It also shares many of the same chemical properties of other rare-earths.
- Scandium is the 35th most abundant element in the Earth’s crust.
- Scandium is the 23rd most abundant element in the Sun.
- Scandium is the first of the transition metals.
- Scandium-46 is a radioisotope used as a tracer to detect leaks in underground pipes. It is also used in oil refining to monitor the process.
- Scandium iodide is used in mercury vapor lights to produce light similar to sunlight to for photography and film.
- The color associated with aquamarine gemstones is due to the presence of scandium.
- Scandium is produced as a byproduct during uranium refinement.
Learn more about elements on the periodic table.