CAS: 7440-62-2
Description: Silvery-white metal
Classification: Transition Metal
Date of Discovery: 1830
Discoverer: Nils Sefstrom
Name Origin:Vanadis, a Scandinavian goddess
Atomic Number: 23
Number of Neutrons: 28
Atomic Mass: 50.9415 amu
Melting Point: 1910 ± 10 °C
Boiling Point: 3407 °C
Density (293 K): 5.8 g/cm3 Atomic volume: 8.78 cm³/mol
Electrical resistivity: 0.0489 10-6/cm Thermal conductivity: 0.307 W/cmK
Enthalpy of atomization: 514.63 kJ/mol
Enthalpy of vaporization: 452 kJ/mol
Enthalpy of fusion: 20.90 kJ/mol
Specific heat capacity: 0.49 J/gK
Energy levels: 2-8-11-2
Electron configuration: [Ar]3d34s2 Crystal Structure: Cubic
Atomic radius: 1.92 Å
Covalent radius: 1.22 Å
Oxidation States: +2, +3, +4, +5
Electronegativity, Pauling: 1.63
Electron affinity: 0.525 eV
First ionization energy: 6.74 eV
2nd ionization energy: 14.65 eV
3rd ionization energy: 29.31 eV
Polarizability: 12.4 10-24cm3
Isotope
Natural Abundance
Atomic Mass
Half-life
Decay Mode
Spin
43V
42.9807
>0.8 s
+
44V
43.9744
0.09 s
+,
45V
44.96578
0.54 s
+
7/2-
46V
45.96020
0.4223 s
+
0+
47V
46.954907
32.6 m
+, EC
3/2-
48V
47.952254
15.98 d
+
4+
49V
48.948517
337 d
EC
7/2-
50V
0.250(2)
49.947163
>1.4 x 1017y
EC, -
6+
51V
99.750(2)
Stable
7/2-
52V
51.944780
3.76 m
-
3+
53V
52.944342
1.61 m
-
7/2-
54V
53.94644
49.8 s
-
3+
55V
54.9472
6.5 s
-
(7/2-)
56V
55.9505
-
57V
56.9525
-
58V
57.9567
-
59V
58.9593
-
60V
59.965
-
61V
Vanadium was first discovered by del Rio in 1801. Unfortunately, a French chemist incorrectly declared del Rio's new element was only impure chromium; del Rio thought himself to be mistaken and accepted the French chemist's statement. The element was rediscovered in 1830 by Sefstrom, who named the element in honor of the Scandinavian goddess Vanadis because of its beautiful multicolored compounds. It was isolated in nearly pure form by Roscoe, in 1867, who reduced the chloride with hydrogen. Vanadium of 99.3 to 99.8% purity was not produced until 1927. Vanadium is found in about 65 different minerals among which are carnotite [K2(UO2)2(VO4)2 · 3H2O], roscoelite [K(V,Al,Mg)2AlSi3O10(OH)2], vanadinite [Pb5(VO4)3Cl], and patronite (VS4) important sources of the metal. Vanadium is also found in phosphate rock and certain iron ores, and is present in some crude oils in the form of organic complexes. It is also found in small percentages in meteorites. Commercial production from petroleum ash holds promise as an important source of the leement. High-purity ductile vanadium can be obtained by reduction of vanadium trichloride with magnesium or with magnesium-sodium mixtures. Much of the vanadium metal being produced is now made by calcium reduction of V2O5 in a pressure vessel, an adaption of a process developed by McKechnie and Seybair. Natural vanadium is a mixture of two isotopes, 50V (0.25%) and 51V (99.75%). 50V is slightly radioactive, having a long half-life. Seventeen other unstable isotopes are recognized. Pure vanadium is a bright white metal, and is soft and ductile. It has good corrosion resistance to alkalis, sulfuric and hydrochloric acid, and salt water, but the metal oxidizes readily above 660 °C. The metal has good structural strength and a low fission neutron cross section, making it useful in nuclear applications. Vanadium is used in producing rust resistant, spring, and highspeed tools steels. It is an important carbide stabilizer in making steels. About 80% of the vanadium now produced is used as ferrovanadium or as a steel additive. Vanadium foil is used as a bonding agent in cladding titanium to steel. Vanadium pentoxide is used in ceramics and as a catalyst. It is also ued in producing a superconductive magnet with a field of 175,000 gauss. Vanadium and its compounds are toxic and should be handled with care. Ductile vanadium is commercially available.
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