The Element Zirconium
[Click for Isotope Data]
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
What's in a name? From the Persian word for gold-like, zargun.
Say what? Zirconium is pronounced as zer-KO-nee-em.
History and Uses:
Zirconium was discovered by Martin Heinrich Klaproth, a German chemist, while analyzing the composition of the mineral jargon (ZrSiO4) in 1789. Zirconium was isolated by Jöns Jacob Berzelius, a Swedish chemist, in 1824 and finally prepared in a pure form in 1914. Obtaining pure zirconium is very difficult because it is chemically similar to hafnium, an element which is always found mixed with deposits of zirconium. Today, most zirconium is obtained from the minerals zircon (ZrSiO4) and baddeleyite (ZrO2) through a process known as the Kroll Process.
Zirconium is a corrosion resistant metal that is used in high performance pumps and valves. Since it also does not easily absorb neutrons, zirconium is widely used in nuclear reactors. The nuclear power industry uses nearly 90% of the zirconium produced each year, which must be nearly free of hafnium. Zirconium is also used as an alloying agent in steel, to make some types of surgical equipment and as a getter, a material that combines with and removes trace gases from vacuum tubes.
Zircon (ZrSiO4) is a zirconium compound that can take many different forms, the most popular of which is a clear, transparent gemstone that can be cut to look like diamond and is frequently used in jewelry. Zirconium dioxide (ZrO2) can withstand very high temperatures and is used to make crucibles and to line the walls of high temperature furnaces. Zirconium carbonate (3ZrO2·CO2·H2O) is used in lotions to treat poison ivy.
Estimated Crustal Abundance: 1.65×102 milligrams per kilogram
Estimated Oceanic Abundance: 3×10-5 milligrams per liter
Number of Stable Isotopes: 4 (View all isotope data)
Ionization Energy: 6.634 eV
Oxidation States: +4
3s2 3p6 3d10
4s2 4p6 4d2