Group 5 (VB): V, Nb, Ta, Db
This page contains brief profiles and pictures of each of the Group 5 metals (VB). More information can be found via the WWW links following each element. However, as these links are to other servers on the Internet you will need to use the BACK button on your browser to return to this page. Credits for the photos and principal links can be found at the end of this document.
Vanadium takes its name from the Scandinavian goddess Vanadis and was discovered in 1801 by AndrÃ©s Manuel del Rio. It was isolated in 1867 by Henry Roscoe as a silvery-white metal that is somewhat heavier than aluminum but lighter than iron. It has excellent corrosion resistance at room temperature.
The history of its discovery is an interesting tale. del Rio sent his brown ore samples, containing what he thought was a new element to Paris for analysis and confirmation, along with a brief explanation that was ambiguous. The complete analysis and description of his work were lost in a shipwreck so the Paris lab saw nothing but brown powder and a brief confusing note. A second sample sent to Berlin was mislabeled lead chromate when it arrived. del Rio gave up, losing confidence in his discovery. The element was rediscovered in 1867 by Nils SefstrÃ´m.
Vanadium has an unusually large number of stable oxidation states (+2, +3, +4, +5)each of which is characterized by a unique color in solution. The metal is used as an alloying agent for steel. It combines with nearly all non-metals in compounds.More background information on V More data on V
Discovered in a museum in 1801, niobium was named after Niobe, the mythological daughter of Tantalus (the metal is chemically related to Tantalum). Occurring in the earth's crust in proportions of about 20 parts-per-million, niobium is used as an alloying agent with iron and nickel. It has commercial uses in atomic reactors and has superconductive properties when alloyed with tin or aluminum.
In many places niobium is known as columbium since it was originally "discovered" in a mineral named columbite. However, careful subsequent analysis indicated that the "new" element was actually Tantalum. The rediscovery of the element we know now as niobium was not even associated with columbium until after the official statistics were in.
Pure niobium looks much like steel but resists corrosion better due to a thin coating of oxide that forms on all exposed surfaces. The only acid that attacks Nb at room temperature is HF. Above 200o the metal becomes more reactive.More background information on Nb More data on Nb
Named for the mythological character Tantalus by Anders Ekenberg who discovered it in 1802, tantalum is a heavy, gray metal that resembles the more expensive platinum in many respects and is sometimes used as an economical substitute for that element. The metal comprises only 0.0002% of the earth's crust and most deposits lie outside the U.S. which is the chief consumer.
Tantalum alloys are corrosion and wear resistant and find use in dental and surgical tools. Tantalum oxide is used in some electronic components and a composite of tantalum carbide (TaC) and graphite is one of the hardest materials ever produced.More background information on Ta More data on Ta
Db no images of Dubnium available
The synthesis of element 105 was reported by Soviet scientists at the research station in Dubna as early as 1967 and by scientists at U.C. Berkeley in 1970. The Soviet scientists reported synthesis by bombarding Am-243 with Ne-22. At Berkeley, Cf-249 was bombarded with N-15.
At the purported time of discovery the Soviets suggested the name Nielsbohrium (Ns) for the element while the American group suggested Hahnium (Ha). But the ensuing controversy over the discovery of this and other 6d-elements led the IUPAC to adopt its numerical system for naming elements beyond 103 until some agreements could be reached (hence Unp or Unnilpentium for 105).
The longest lived isotope has a half-life of 34 seconds.
Dubnium is the name approved by the IUPAC in August 1997.More background information on Db More data on Db
Sources: Photos of the elements were taken from the LIFE Science Library book Matter. Background links go to the Periodic Table created at Los Alamos National Laboratories by Robert Husted. Data links go to the primary site of Mark Winter's WebElements, version 2.0, at the University of Sheffield in the United Kingdom.