• Class: Transition Metals
• Period: 5
• IUPAC group: 4
• Traditional: IVa

• Discovered in: 1789 by Klaproth
• Origin of name: Arabic zargun, (gold color)
• Historical or alternate name:

Zircon, baddeleyite & 30 other minerals

Lustrous, hard, silvery metal. Exposed surfaces form oxide protective film. Metallic compounds may be soft and malleable.

• Atmosphere: ~0.0 ppm
• Primitive mantle: 8.3 ppm
• Sea water: 2.6e-5 ppm
• Metallic meteorite: 3.69 ppm
• Continental crust: 100.0 ppm
• Solar photosphere: 2.75 log of abundance
• Oceanic crust: 80.0 ppm
• Solar system: 10.7 relative to Si=1.0e6

   Hazards

Flammable solid. Ignites and reacts violently with oxidants..

   Human daily limits

• Lower:1.0
• Upper:100.0

Zirconium Physical Properties

 Transitional Data

• State: Solid
• Density: 6.49 g/cm3

 Molar enthalpy

• Atomization: 607.47 kJ mol-1
• Fusion: 23.0 kJ mol-1
• Vaporization: 566.7 kJ mol-1

 Transition points

• Melting point: 2125.0 K
• Boiling point: 4650.0 K
• Critical temperature: 8650.0 K

 Molar properties

• Atomic weight: 91.224 g/mole
• Molar volume: 14.106 cm3 mol-1

 Crystal structure sequence

hexagonal-close-packed <1138 K < body-centered-cubic < melting point

 Thermodynamics

• State: solid
  • Enthalpy 0
  • Gibbs function 0
  • Entropy 38.99
  • Heat Capacity 25.36

• State: gas
  • Enthalpy 608.8
  • Gibbs function 566.5
  • Entropy 181.36
  • Heat Capacity 26.65

 Miscellaneous physical

• Electrical resistivity: 42.1 µ-ohms/cm
• Debye temperature: 291.0 K
• Thermal conductivity: 22.7 W / m / K
• Coefficient of linear expansion: 5.7Coef. per K
• Mass magnetic susceptibility: 1.68e-8
• X-ray diffraction mass absorption coefficients:
• CuK: 143 (µ/p)/cm2 g-1
• MoK: 15.9 (µ/p)/cm2 g-1

Zirconium Chemical Properties

 Chemical basics:

• Oxidation states: +4
• Molecular wt: 91.224 g/mole

 Radii

• Covalent: 145 pm
• Atomic: 160.0 pm
• Van der Waals: pm

 Ions:

• ion: +4 pm 72.0

 Covalent bonds

 Effective nuclear charge

• Slater: 3.15
• Clementi: 6.45
• Froese-Fischer: 9.20

 Electronegativity

• Pauling: 1.4
• Allred-Rochow: 1.22

 Standard reactions

Zirconium Nuclear Properties

• Known 20
• Listed 8

• Known 81 - 98
• Listed 88 - 96

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 83.4 days
  • Decay mode: E.C.,
  • Source: reactor
• Notes

• % Occ.:Natural 51.45%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 11.22%
• Mossbauer NRA:
• Nuclear spin/Quantum no.: 5/2
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural 17.15%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.: 5/2
• Radioisotopes:
  • Half-life: 1.5 E6 years
  • Decay mode: Beta-
  • Source: reactor
• Notes

• % Occ.:Natural 17.38%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• % Occ.:Natural
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life: 64.0 days
  • Decay mode: Beta-
  • Source: reactor
• Notes

• % Occ.:Natural 2.80%
• Mossbauer NRA:
• Nuclear spin/Quantum no.:
• Radioisotopes:
  • Half-life:
  • Decay mode:
  • Source:
• Notes

• Isotope Cross-section 0.182±0.005 barns

• Absolute sensitivity: 1.06e-3 1H=1.0
• Relative sensitivity: 9.48e-3 1H=1.0
• Receptivity: 6.04 13C=1.0
• Magnetogyric ratio: -2.4868e7 rad / T / s
• Quadropole moment: -0.21e-28 m2
• Frequency: 9.330 MHz
• Reference:

Zirconium Energy Properties

Electrons

• Ground state electron configuration: [Kr] 4d2 5s2
• Electron affinity: 43 kJ mol-1
• Filling orbitals:

Spectral lines

 Ionization energies

 Atomic energy levels