Zirconium



40 niobium
Hf
General
Number zirconium, Zr, 40
transition metals
Block d
Appearance silvery white
(2)  g·mol−1
Kr] 4d2 5s2
shell 2, 8, 18, 10, 2
Physical properties
Phase solid
r.t.) 6.52  g·cm−3
Liquid m.p. 5.8  g·cm−3
F)
F)
kJ·mol−1
kJ·mol−1
Heat capacity (25 °C) 25.36  J·mol−1·K−1
Vapor pressure
P(Pa) 1 10 100 1 k 10 k 100 k
at T(K) 2639 2891 3197 3575 4053 4678
Atomic properties
hexagonal close-packed
amphoteric oxide)
Electronegativity 1.33 (Pauling scale)
more) 1st:  640.1  kJ·mol−1
2nd:  1270  kJ·mol−1
3rd:  2218  kJ·mol−1
Atomic radius 155  pm
Atomic radius (calc.) 206  pm
Covalent radius 148  pm
Miscellaneous
Magnetic ordering no data
Electrical resistivity (20 °C) 421 n Ω·m
Thermal conductivity (300 K) 22.6  W·m−1·K−1
Thermal expansion (25 °C) 5.7  µm·m−1·K−1
Speed of sound (thin rod) (20 °C) 3800 m/s
Young's modulus 68  GPa
Shear modulus 33  GPa
Poisson ratio 0.34
Mohs hardness 5.0
Vickers hardness 903  MPa
Brinell hardness 650  MPa
CAS registry number 7440-67-7
Selected isotopes
Main article: Isotopes of zirconium
iso NA half-life DM DE (MeV) DP
88Zr syn 83.4 d ε - 88Y
γ 0.392D -
89Zr syn 78.4 h ε - 89Y
β+ 0.902 89Y
γ 0.909D -
90Zr 51.45% Zr is neutrons
91Zr 11.22% Zr is neutrons
92Zr 17.15% Zr is neutrons
93Zr syn 1.53×106y β− 0.060 93Nb
94Zr 17.38% Zr is neutrons
96Zr 2.8% 2.0×1019y [3] β−β− 3.348 96Mo
References

Zirconium (corrosion.

Characteristics

Zirconium is a grayish-white oxidation state of zirconium is usually +4, although +3 and +2 can also be obtained inside of chemical compounds.

History

Zirconium (from Syriac zargono,[4] Arabic zarkûn from Persian zargûn زرگون meaning "gold like") was Jöns Jakob Berzelius.

The zirconium-containing mineral zircon, or its variations (jargon, hyacinth, jacinth, or ligure), were mentioned in biblical writings. The mineral was not known to contain a new element until Klaproth analyzed a jargon from the island of Ceylon in the Indian Ocean. He named the new element Zirkonertz (zirconia). The impure metal was isolated first by Berzelius by heating a mixture of potassium and potassium-zirconium fluoride in a small decomposition process conducted in an iron tube. Pure zirconium wasn't prepared until 1914.

The Kroll process.

Occurrence

    Zirconium is never found in nature as a native metal. The principal economic source of zirconium is the zirconium Kroll process. Commercial-quality zirconium for most uses still has a content of 1% to 3% hafnium.

This element is relatively-abundant in S-type stars, and it has been detected in the sun and in meteorites. Lunar rock samples brought back from several Apollo program missions to the moon have a quite high zirconium oxide content relative to terrestrial rocks.

See also zirconium minerals.

Isotopes

Main article: isotopes of zirconium

Naturally-occurring zirconium is composed of four stable isotopes, and one extremely long-lived beta decay. Other isotopes of zirconium include 90Zr, 91Zr, and 94Zr

Compounds

Some common zirconium compounds are: ZrC, ZrO2, ZrN, ZrCl4, ZrS2, ZrSi2, ZrSiO4, ZrF4, ZrBr4, ZrI4, Zr(OH)4, C10H11ClZr, Zr(CH3CH2COO)4, Zr(WO4)2, ZrH2, Pb(ZrxTi1-x)O3

Precautions

  Compounds containing zirconium are not noted for toxicity. The metal dust can ignite in air and should be regarded as a major fire and explosion hazard. Zirconium has no known biological role.

References

  • Los Alamos National Laboratory – Zirconium
  1. ^ Zirconium: zirconium(III) iodide compound data. WebElements.com. Retrieved on 2007-12-10.
  2. ^ Zirconium: zirconium(I) fluoride compound data. OpenMOPAC.net. Retrieved on 2007-12-10.
  3. ^ Double Beta Decay Transitions
  4. ^ http://www.tertullian.org/rpearse/oriental/syriac.htm
 
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