Vanadium

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Vanadium,  23V
General properties
Name, symbol Vanadium, V
Appearance Silvery-gray metal
Vanadium in the periodic table
-

V

Nb
Titanium ← Vanadium → Chromium
Atomic number 23
Standard atomic weight (Ar) 50.9415(1)
Group, block , d-block
Period period 4
Electron configuration [Ar] 3d3 4s2
per shell
2, 8, 11, 2
Physical properties
Silvery-gray
Phase Solid
Melting point 2183 K ​(1910 °C, ​​3470 °F)
Boiling point 3680 K ​(3407 °C, ​6165 °F)
Density near r.t. 6.0 g/cm3
when liquid, at  5.5 g/cm3
Heat of fusion 21.5 kJ/mol
Heat of 444 kJ/mol
Molar heat capacity 24.89 J/(mol·K)
 pressure
Atomic properties
Oxidation states +5, +4, +3, +2, +1, −1, −3 ​(an amphoteric oxide)
Electronegativity Pauling scale: 1.63
energies 1st: 650.9 kJ/mol
2nd: 1414 kJ/mol
3rd: 2830 kJ/mol
Atomic radius empirical: 134 pm
Covalent radius 153±8 pm
Miscellanea
Crystal structure ​​body-centered cubic (bcc)
Speed of sound thin rod 4560 m/s (at 20 °C)
Thermal expansion 8.4 µm/(m·K) (at 25 °C)
Thermal conductivity 30.7 W/(m·K)
Electrical resistivity 197 Ω·m (at 20 °C)
Magnetic ordering Paramagnetic
Young's modulus 128 GPa
Shear modulus 47 GPa
Bulk modulus 160 GPa
Poisson ratio 0.37
Mohs hardness 6.7
Vickers hardness 628–640 MPa
Brinell hardness 600–742 MPa
CAS Registry Number 7440-62-2
History
Discovery Andrés Manuel del Río (1801)
First isolation Nils Gabriel Sefström (1830)
Named by Nils Gabriel Sefström (1830)
· references

Vanadium is a chemical element with symbol V and atomic number 23. It is mainly used in industry for high strength steels.

Properties

Chemical

It has good resistance to corrosion and it is stable against alkali and sulfuric and hydrochloric acids.[12] It is oxidized in air at about 933 K (660 °C, 1220 °F), although an oxide layer forms even at room temperature.

Physical

Vanadium is a medium-hard, ductile, malleable, strong silvery-gray or steel-blue metal. Vanadium is harder than most pure metals and common steels. Vanadium has a high melting point of 1910 °C and boils at 3407 °C. Vanadium is lighter than steel, with a density of 6 g/cm3.

Availability

Vanadium is sold by various chemical suppliers.

It can also be extracted from chromium-vanadium steels, generally encountered in tools and other devices. Ferrovanadium is also a source.

Isolation

In industries is Vanadium metal is obtained via a multistep process that begins with the roasting of crushed ore with NaCl or Na2CO3 at about 850 °C to give Sodium metavanadate (NaVO3). An aqueous extract of this solid is acidified to give "red cake", a polyvanadate salt, which is reduced with calcium metal. Vanadium can be also obtained by reducing vanadium pentoxide with aluminium, magnesium, or hydrogen. Note that aluminum is soluble in vanadium, so to isolate pure metal one must not use an excess of aluminum. Magnesium does not share this level of solubility in vanadium metal, but the reaction between V2O5 and Mg is sufficiently energetic to boil the V metal produced.

Pure vanadium metal can be obtained through the thermal decomposition of vanadium(III) iodide:

2 V + 3 I2 ⇌ 2 VI3

Projects

  • Make vanadium pentoxide
  • Make various high strength steels

Handling

Safety

Vanadium compounds show toxicity and should be handled with care.

Storage

Vanadium should be stored in closed containers.

Vanadium powder should be stored away from air.

Disposal

Vanadium should be taken to disposal facilities.

References

Elementcollector1: Isolation notes based on experience, feel free to argue.

Relevant Sciencemadness threads