Group 5

Group 5 (also known as Group 5 of the transition metals) is one of the six columns of transition metals in the chemical periodic table. It contains vanadium (V), niobium (Nb), tantalum (Ta), and dubnium (Db). All are transition metals, meaning their electron configuration includes a filled d subshell.

The elements in this group share five electrons in their outermost electron shell (valence electrons). For this reason, they typically exhibit an oxidation state of +5, particularly niobium and tantalum. Vanadium, by contrast, can readily adopt multiple oxidation states such as +2, +3, +4, and +5, which gives it different colors when in solution.

General physical properties

The three naturally occurring elements—vanadium, niobium, and tantalum—are hard metals with a silvery-white color and very high melting points. Tantalum and niobium are notable for their corrosion resistance, as their surfaces form a protective oxide layer that shields the underlying metal. Density increases as one moves down the group: tantalum is considerably denser than vanadium.

Niobium and tantalum have very similar atomic radii, a consequence of the lanthanide contraction effect. This is why the two elements behave very similarly, and their separation from one another in ores is a difficult and lengthy process.

Industrial uses

Vanadium is chiefly added to steel to produce strong alloys that resist impact and heat; it is also used as a catalyst in certain chemical processes. Niobium is used in superconducting alloys and hard structural steels. Tantalum is used in electronic components, especially capacitors in small devices, and in medical implants, because it does not react with body tissues.

Dubnium

Dubnium is a synthetic element not found naturally in the earth. It is produced in particle accelerators by colliding heavy atoms. All of its isotopes are radioactive with very short half-lives, so it has no industrial applications; research into it is confined to small-scale laboratory experiments.