Vanadium

Vanadium, pronounced veh-NAY-di-em, atomic symbol V, and atomic number associated with this transition metal is 23. The atomic weight of Vanadium is 50.942 grams per one mole. The electron configuration is 1S2 2S2 2P6 3S2 3P6 4S2 3D3 and the noble gas notation is [Ar] 4S2 3D3.

Vanadium is located in group 5B, in the transition metals, on the periodic table of the elements. Also, included in this group are niobium [atomic number 41 with an atomic weight of 92.9064 grams per mole], tantalum [atomic number 73 with an atomic weight of 180.948 grams per mole], and dubnium [atomic number 105 with an atomic weight of 262.114 grams per mole].

With a smaller density than its two counter parts, that we have data referencing, vanadium also has a lower melting point and boiling point. Since "the atomic size increases down a group," as we learned in chapter ten of Zumdahl's text, the vanadium atom is smaller than niobium and tantalum, respectively. Likewise, Zumdahl explained that, "the ionization energies decrease down a group," vanadium contains higher ionization energy and is, overall, more pliable than niobium or tantalum.

Vanadium Niobium Tantalum

Melting Point 1900◦C/3500◦F +/-10◦ 2470◦C/4490◦F +/-10◦ 3010◦C/5460◦F +/-10◦

Boiling Point 3380◦C/5400◦ F +/- 10◦ 4740◦C/8570◦F +/-10◦ 5450◦C/9850◦F +/-10◦

Molar Mass 8.32 / cm^3 10.83 / cm^3 10.85 / cm^3

Geologically, the amount of naturally occurring vanadium is twenty-five hundredths of one percent (0.250 %). This is much lower than niobium and tantalum, which are found to be one hundred percent and ninety-nine and nine hundred eighty-eight thousandths of one percent (100% and 99.988%) naturally occurring, respectively. Vanadium is not found as a free metal in nature, which is a trait that it shares with dubnium. However, natural vanadium is a mixture of two isotopes [^50V (0.24%) and ^51V (99.76%)] and it can be found in over fifty different minerals; some of the minerals containing vanadium are: the ore carnotite combined with uranium [K2(UO2)2(VO4)2.3H2O]; lead is combined with vanadium in vanadanite [Pb5(VO4)3Cl]; and sulfur combined with vanadium in patronite (VS4). It is also present in deposits containing carbon such as crude oils, coal, oil shale, and tar sands. This information seems almost contradictory but the quantity, of this element, that can actually found in these minerals are minimal.

This is rather interesting considering the parts per billion (by weight) of vanadium that can be found in the universe, in crustal rocks, and in sea water and in comparison to niobium and tantalum.

Vanadium Niobium Tantalum

Universe 1,000 ppb 2 ppb 0.8 ppb

Crustal Rocks 190,000 ppb 17,000 ppb 1,700 ppb

Sea Water 1.5 ppb 0.001 ppb 0.002 ppb

For an element, like vanadium, to have a much smaller likelihood, compared to other members of its group, to be found naturally occurring, it is rather intriguing that the parts per billion of that element that can be found in the universe of this element is much greater than that of an element that is said to be one-hundred percent naturally occurring, niobium. Vanadium is the nineteenth most abundant element in the Earth's crust.

Of further interest, vanadium is the only element, of group 5B, to be found, at all, in the human body, with thirty parts per billion (by weight). In meteorites, Vanadium has also been uncovered, in minute percentages, and the spectra of vanadium have been detected, in light from some stars and from the sun. It is absolved instinctively into the air, by the formation "of continental dust, marine aerosols, and volcanic emissions."

Usually the releases, from combustion of fossil fuels, are in the structure of vanadium oxides, which are responsible for close to two-thirds of the vanadium found in out atmosphere. The level of vanadium in the atmosphere is currently low, but, the World Health Organization states, "it is suspected that air concentrations will increase in the future as a function of accelerated fossil-fuel combustion in rural areas." That is just one more emission control problem that we should watch out for.

The physical appearance of tantalum would be the greatest difference in this group; it is grayish-silver, heavy, and a very hard metal but it is also similar as it is ductile. Whereas the appearance of vanadium and niobium are more similar; they both are bright white and are soft, ductile metals. The meaning of ductile, as per the on-line reference dictionary.com, means that the metal can be easily molded, shaped, and/or hammered thin. Vanadium and niobium are, therefore, very useful due to the ductility of the metal.

Niobium and tantalum come in many different forms such as sheet, foil, insulated wire, powder, rod, and tube and the niobium minerals usually contain both niobium and tantalum as it is difficult to separate them due to the chemical similarities between the two. The major uses for niobium and tantalum are in chemical processing, lighting, and in capacitors.

One of the main uses for vanadium is as a steel additive to produce alloys due to the structural strength and corrosion resistance. Steel is augmented by the addition of vanadium due to the rigidity at high temperatures and the aptitude to resist shock. It is used in the production of rust-resistant springs, surgical instruments and is an important carbide stabilizer for tool steels; over eighty percent (80%) of the world's expenditure of vanadium, which exceeds thirty thousand (30,000) tons, is due to the steel industry. As a foil, it is used to bond titanium steel and aluminum used in jet engines and high-speed airframes. A vanadium compound, such as vanadium pentoxide (V2O5), is used as a catalyst to modify and increase the rate of chemical reaction in the ceramics industry, and in the manufacturing process of aniline black; aniline is used for resins, dyes, and varnishes. At specific temperatures, infrared radiation is blocked with glass that is coated with a vanadium compound, specifically vanadium dioxide. Additionally, as it has also a low fission neutron cross-section, a lower energy level as it splits into parts. This information, in combination with the fact that vanadium allows neutrons to penetrate easily, yet repels advances from many chemicals, makes it useful in nuclear reactor applications.

This is a beneficial element