Atomic number:40

Group numbers:4

Period:5

Electronic configuration:[Kr] 4d² 5s²

Formal oxidation number:+4

Electronegativities:1.33

Atomic radius / pm:159

Relative atomic mass:91.224 ± 0.002

 

Zirconium was discovered by Martin Heinrich Klaproth (DE) in 1789. The origin of the name comes from the Arabic word zargun meaning gold colour. It is a grey-white, lustrous, corrosion-resistant metal. Exposed surfaces form oxide protective film. Zirconium is found in many minerals such as zircon and baddeleyite. It is used in alloys such as zircaloy which is used in nuclear applications since it does not readily absorb neutrons. Zirconium is used in high-performance pumps and valves. Clear zircon (ZrSiO4) is a popular gemstone.

Density / g dm^-3:6506 (293 K)

 5800 (m.p.)

Molar volume / cm³mol^-1:14.02 (293 K)

 15.73 (m.p.)

Electrical resistivity / μΩcm:42.1 (20 °C)

Thermal conductivity / W m^-1K^-1:22.7

Melting point / °C:1855

Boiling point / °C:4409

Heat of fusion / kJ mol^-1:23

Heat of vaporization / kJ mol^-1:566.7

Heat of atomization / kJ mol^-1:607.47

1st ionization energy / kJ mol^-1:640.08

2nd ionization energy / kJ mol^-1:1266.86

3rd ionization energy / kJ mol^-1:2218.21

in the atmosphere / ppm:-

in the Earth's crust / ppm:100

in the oceans / ppm:0.000026