Element 51: Scandium

Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic d-block element, it has historically been classified as a rare earth element, together with yttrium and the lanthanides. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia.

Physical and Chemical Properties

Scandium is a relatively soft metal with a silvery-white appearance. It is a light element, with a density similar to that of aluminum. Scandium has a high melting point and boiling point, and is a good conductor of electricity and heat.

Scandium is a reactive metal, reacting with air to form a thin oxide layer on its surface. It also reacts with water and acids, and is soluble in many acids, including hydrochloric and sulfuric acid. Scandium is not found in nature as a free element, but is found in small amounts in minerals such as scandium, thortveitite, and wolframite.

Uses

The primary use of scandium is as an alloying element in the production of high-strength aluminum alloys used in aerospace and defense applications. Scandium-aluminum alloys increase the strength and durability of the aluminum, while also reducing weight. Scandium is also used in the production of high-intensity lamps and lasers, as a neutron source in nuclear reactors, and in the production of specialty ceramics and glass.

Scandium has recently gained attention as a potential material for energy storage, particularly in rechargeable batteries. Research is ongoing to develop scandium-based rechargeable batteries with higher energy densities and longer lifetimes than traditional lithium-ion batteries.