Atomic Number: 40
Atomic Weight: 91.224
Melting Point: 2128 K (1855°C or 3371°F)
Boiling Point: 4682 K (4409°C or 7968°F)
Density: 6.52 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 5
Group Number: 4
Group Name: none
Zirconium has five stable isotopes, of which a few are used for the production of radioisotopes. Although radioactive Zr-95 is a fission product, it can also produced by neutron irradiation of Zr-94. Zr-96 has been used for the production of the radioisotope Zr-97. Zr-90 can be used for the production of the PET isotope Nb-90. Finally, Zr-90 has been proposed for cladding in nuclear fuel. The use of Zr-90 would lower even further the already low neutron absorption cross section of natural Zr that is currently used as fuel cladding.