| Atomic Mass | 91.224 |
|---|---|
| Electron Configuration | [Kr]5s24d2 |
| Oxidation States | +4 |
| Year Discovered | 1789 |
| Atomic Mass | 91.224 |
|---|---|
| Electron Configuration | [Kr]5s24d2 |
| Oxidation States | +4 |
| Year Discovered | 1789 |
| Element Name | Zirconium |
|---|---|
| Element Symbol | Zr |
| InChI | InChI=1S/Zr |
| InChIKey | QCWXUUIWCKQGHC-UHFFFAOYSA-N |
| Atomic Weight |
91.222(3) 91.224 91.22 91.224(2) |
|---|---|
| Electron Configuration |
[Kr]5s24d2 |
| Atomic Radius |
Van der Waals Atomic Radius : 186 pm (Van der Waals) Empirical Atomic Radius : 155pm (Empirical) Covalent Atomic Radius : 175(7) pm (Covalent) |
| Oxidation States |
+4 4, 3, 2, 1, -2 (an amphoteric oxide) |
| Ground Level |
3F2 |
| Ionization Energy |
6.634 eV 6.634126 ± 0.000005 eV |
| Electronegativity |
Pauling Scale Electronegativity : 1.33(Pauling Scale) Allen Scale Electronegativity : 1.32(Allen Scale) |
| Electron Affinity |
0.426eV 0.45eV |
| Atomic Spectra |
Lines Holdings Levels Holdings |
| Physical Description |
Solid |
| Element Classification |
Metal |
| Element Period Number |
5 |
| Element Group Number |
4 |
| Density |
6.52 grams per cubic centimeter |
| Melting Point |
2128 K (1855°C or 3371°F) 1855°C |
| Boiling Point |
4682 K (4409°C or 7968°F) 4377°C |
| Estimated Crustal Abundance |
1.65×102 milligrams per kilogram |
| Estimated Oceanic Abundance |
3×10-5 milligrams per liter |
The name derives from the Arabic zargun for "gold-like". It was discovered in zirconia by the German chemist Martin-Heinrich Klaproth in 1789. Zirconium was first isolated by Swedish chemist Jöns Jacob Berzelius in 1824 in an impure state, and finally by the chemists D. Lely, Jr. and L. Hamburger in a pure state in 1914.
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.
From the Persian zargun, gold like. Zircon, the primary gemstone of zirconium, is also known as jargon, hyacinth, jacinth, or ligure. This mineral, or its variations, is mentioned in biblical writings. The mineral was not known to contain a new element until Klaproth, in 1789, analyzed a jargon from Ceylon and identified the new element, which Werner named zircon (silex circonius), and which Klaproth called Zirkonertz (zirconia). The impure metal was first isolated by Berzelius in 1824 by heating a mixture of potassium and potassium zirconium fluoride in a small decomposition process they developed.
| Year | Atomic Weight (uncertainty) [u] | Reference |
|---|---|---|
| 2024 | 91.222(3) | |
| 1983 | 91.224(2) | https://doi.org/10.1351/pac198456060653 |
| 1969 | 91.22(1) | https://doi.org/10.1351/pac197021010091 |
| 1931 | 91.22 | https://doi.org/10.1039/JR9310001617 |
| 1925 | 91 | https://doi.org/10.1039/CT9252700913 |
| 1903 | 90.6 | https://doi.org/10.1021/ja02003a001 |
| 1902 | 90.7 | https://doi.org/10.1007/BF01370337 |
Reactor-grade zirconium is essentially free of hafnium. Zircaloy(R) is an important alloy developed specifically for nuclear applications. Zirconium is exceptionally resistant to corrosion by many common acids and alkalis, by sea water, and by other agents. Alloyed with zinc, zirconium becomes magnetic at temperatures below 35°K.
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.
It is used extensively by the chemical industry where corrosive agents are employed. Zirconium is used as a getter in vacuum tubes, as an alloying agent in steel, in surgical appliances, photoflash bulbs, explosive primers, rayon spinnerets, lamp filaments, etc. It is used in poison ivy lotions in the form of the carbonate as it combines with urushiol. With niobium, zirconium is superconductive at low temperatures and is used to make superconductive magnets, which offer hope of direct large-scale generation of electric power. Zirconium oxide (zircon) has a high index of refraction and is used as a gem material. The impure oxide, zirconia, is used for laboratory crucibles that will withstand heat shock, for linings of metallurgical furnaces, and by the glass and ceramic industries as a refractory material. Its use as a refractory material accounts for a large share of all zirconium consumed.
Zirconium is produced from the mineral zircon (ZrSiO4). It is found in abundance in S-type stars, and has been identified in the sun and meteorites. Analysis of lunar rock samples obtained during the various Apollo missions to the moon show a surprisingly high zirconium oxide content, compared with terrestrial rocks.
See more information at the Zirconium compound page.
| CID | Name | Formula | SMILES | Molecular Weight |
|---|---|---|---|---|
| 23995 | zirconium | Zr | [Zr] | 91.22 |
| 115139 | zirconium(4+) | Zr+4 | [Zr+4] | 91.22 |
| 178156 | zirconium-89 | Zr | [89Zr] | 88.90888 |
| 91573 | zirconium-95 | Zr | [95Zr] | 94.908040 |
| 119436 | zirconium-93 | Zr | [93Zr] | 92.906471 |
| 177444 | zirconium-88 | Zr | [88Zr] | 87.91022 |
| 167206 | zirconium-97 | Zr | [97Zr] | 96.910964 |
| 177659 | zirconium-86 | Zr | [86Zr] | 85.91630 |
| 10313072 | zirconium-90 | Zr | [90Zr] | 89.904699 |
| 4281183 | zirconium(2+) | Zr+2 | [Zr+2] | 91.22 |
| 21981402 | zirconium(3+) | Zr+3 | [Zr+3] | 91.22 |
| 109374074 | zirconium-89(4+) | Zr+4 | [89Zr+4] | 88.90888 |
| 10197631 | zirconium-94(4+) | Zr+4 | [94Zr+4] | 93.906313 |
| 10197632 | zirconium-94 | Zr | [94Zr] | 93.906313 |
| 10313071 | zirconium-90(4+) | Zr+4 | [90Zr+4] | 89.904699 |
| 131708408 | zirconium-91 | Zr | [91Zr] | 90.905640 |
| 131708409 | zirconium-92 | Zr | [92Zr] | 91.905035 |
| 131708410 | zirconium-96 | Zr | [96Zr] | 95.908278 |
| Stable Isotope Count | 4 |
|---|---|
| Summary | Naturally occurring zirconium contains five isotopes. Fifteen other isotopes are known to exist. Zircon, ZrSiO4, the principal ore, is pure ZrO2 in crystalline form having a hafnium content of about 1%. Zirconium also occurs in some 30 other recognized mineral species. Zirconium is produced commercially by reduction of chloride with magnesium (the Kroll Process), and by other methods. It is a grayish-white lustrous metal. When finely divided, the metal may ignite spontaneously in air, especially at elevated temperatures. The solid metal is much more difficult to ignite. The inherent toxicity of zirconium compounds is low. Hafnium is invariably found in zirconium ores, and the separation is difficult. |
Zirconium enriched in 90Zr has been proposed for the cladding (covering) of reactor fuel elements (Fig. IUPAC.40.1) because it has a lower neutron absorption cross section than natural abundances of zirconium and is well suited for coverage of metal parts without absorbing neutrons [307].
![Fig. IUPAC.40.1: The cores of nuclear reactors have fuel pins that are typically made of uranium-oxide. To keep fission products from escaping into the coolant, these pins are surrounded by zirconium cladding. (Modified from [308]).](https://pubchem.ncbi.nlm.nih.gov/images/iupac/j_pac-2015-0703_fig_060.jpg)
| Isotope | Atomic Mass (uncertainty) [u] | Abundance (uncertainty) |
|---|---|---|
| 90Zr | 89.904 6988(8) | 0.5147(6) |
| 91Zr | 90.905 6402(7) | 0.1123(6) |
| 92Zr | 91.905 0353(7) | 0.1716(4) |
| 94Zr | 93.906 313(1) | 0.1736(7) |
| 96Zr | 95.908 2776(8) | 0.0278(4) |
| Isotope | Atomic Mass (uncertainty) [u] | Abundance (uncertainty) |
|---|---|---|
| 90Zr | 89.9046977(20) | 0.5145(40) |
| 91Zr | 90.9056396(20) | 0.1122(5) |
| 92Zr | 91.9050347(20) | 0.1715(8) |
| 94Zr | 93.9063108(20) | 0.1738(28) |
| 96Zr | 95.9082714(21) | 0.0280(9) |
| Nuclide | Atomic Mass and Uncertainty [u] | Half Life and Uncertainty | Discovery Year | Decay Modes, Intensities and Uncertainties [%] |
|---|---|---|---|---|
| 77Zr | 76.966076 ± 0.000429 [Estimated] | 100 us [Estimated] | 2017 | β+ ?; β+p ?; p ? |
| 78Zr | 77.956146 ± 0.000429 [Estimated] | 50 ms >200ns [Estimated] | 2001 | β+ ?; β+p ? |
| 79Zr | 78.949790 ± 0.000322 [Estimated] | 56 ms ± 30 | 1999 | β+=100%; β+p ? |
| 80Zr | 79.941213 ± 0.000322 [Estimated] | 4.6 s ± 0.6 | 1987 | β+=100% |
| 81Zr | 80.938245000 ± 0.000099 | 5.5 s ± 0.4 | 1997 | β+=100%; β+p=0.12±0.2% |
| 82Zr | 81.931707497 ± 0.0000017 | 32 s ± 5 | 1982 | β+=100% |
| 83Zr | 82.929240926 ± 0.000006902 | 42 s ± 2 | 1974 | β+=100%; β+p=? |
| 83Zrm | 82.929240926 ± 0.000006902 | 530 ns ± 120 | 1988 | IT=100% |
| 83Zrn | 82.929240926 ± 0.000006902 | 1.8 us ± 0.1 | 1988 | IT=100% |
| 84Zr | 83.923325663 ± 0.000005903 | 25.8 m ± 0.5 | 1977 | β+=100% |
| 85Zr | 84.921443199 ± 0.000006902 | 7.86 m ± 0.04 | 1963 | β+=100% |
| 85Zrm | 84.921443199 ± 0.000006902 | 10.9 s ± 0.3 | 1976 | IT=?; β+=? |
| 86Zr | 85.916296814 ± 0.000003827 | 16.5 h ± 0.1 | 1951 | β+=100% |
| 87Zr | 86.914817338 ± 0.00000445 | 1.68 h ± 0.01 | 1948 | β+=100% |
| 87Zrm | 86.914817338 ± 0.00000445 | 14.0 s ± 0.2 | 1972 | IT=100% |
| 88Zr | 87.910220715 ± 0.0000058 | 83.4 d ± 0.3 | 1951 | ε=100% |
| 88Zrm | 87.910220715 ± 0.0000058 | 1.320 us ± 0.025 | 1978 | IT=100% |
| 89Zr | 88.908879751 ± 0.000002983 | 78.360 h ± 0.023 | 1948 | β+=100% |
| 89Zrm | 88.908879751 ± 0.000002983 | 4.161 m ± 0.010 | 1953 | IT=93.77±1.2%; β+=6.23±1.2% |
| 90Zr | 89.904698755 ± 0.000000126 | Stable | 1924 | IS=51.45±0.4% |
| 90Zrm | 89.904698755 ± 0.000000126 | 809.2 ms ± 2.0 | 1972 | IT=100% |
| 90Zrn | 89.904698755 ± 0.000000126 | 131 ns ± 4 | 1977 | IT=100% |
| 91Zr | 90.905640205 ± 0.000000101 | Stable | 1934 | IS=11.22±0.5% |
| 91Zrm | 90.905640205 ± 0.000000101 | 4.35 us ± 0.14 | 1985 | IT=100% |
| 92Zr | 91.905035336 ± 0.000000101 | Stable | 1924 | IS=17.15±0.3% |
| 93Zr | 92.906470661 ± 0.000000489 | 1.61 My ± 0.05 | 1950 | β-=100% |
| 94Zr | 93.906312523 ± 0.000000175 | Stable >110Py | 1924 | IS=17.38±0.4%; 2β- ? |
| 95Zr | 94.908040276 ± 0.000000933 | 64.032 d ± 0.006 | 1946 | β-=100% |
| 96Zr | 95.908277615 ± 0.000000122 | 23.4 Ey ± 1.7 | 1934 | IS=2.80±0.2%; 2β-=100% |
| 97Zr | 96.910963802 ± 0.00000013 | 16.749 h ± 0.008 | 1951 | β-=100% |
| 97Zrm | 96.910963802 ± 0.00000013 | 104.8 ns ± 1.7 | 1976 | IT=100% |
| 98Zr | 97.912740448 ± 0.000009065 | 30.7 s ± 0.4 | 1967 | β-=100% |
| 98Zrm | 97.912740448 ± 0.000009065 | 1.9 us ± 0.2 | 2005 | IT=100% |
| 99Zr | 98.916675081 ± 0.000011271 | 2.1 s ± 0.1 | 1970 | β-=100% |
| 99Zrm | 98.916675081 ± 0.000011271 | 336 ns ± 5 | 1970 | IT=100% |
| 100Zr | 99.918010499 ± 0.000008742 | 7.1 s ± 0.4 | 1970 | β-=100% |
| 101Zr | 100.921458454 ± 0.000008944 | 2.29 s ± 0.08 | 1972 | β-=100% |
| 102Zr | 101.923154181 ± 0.000009401 | 2.01 s ± 0.08 | 1970 | β-=100% |
| 103Zr | 102.927204054 ± 0.0000099 | 1.38 s ± 0.07 | 1987 | β-=100%; β-n<1% |
| 104Zr | 103.929449193 ± 0.00001 | 920 ms ± 28 | 1990 | β-=100%; β-n<1% |
| 105Zr | 104.934021832 ± 0.000013 | 670 ms ± 28 | 1992 | β-=100%; β-n<2% |
| 106Zr | 105.936930 ± 0.000215 [Estimated] | 179 ms ± 6 | 1994 | β-=100%; β-n<7% |
| 107Zr | 106.942007 ± 0.000322 [Estimated] | 145.7 ms ± 2.4 | 1994 | β-=100%; β-n<23% |
| 108Zr | 107.945303 ± 0.000429 [Estimated] | 78.5 ms ± 2.0 | 1997 | β-=100%; β-n ? |
| 108Zrm | 107.945303 ± 0.000429 [Estimated] | 540 ns ± 30 | 2011 | IT=100% |
| 109Zr | 108.950907 ± 0.000537 [Estimated] | 56 ms ± 3 | 1997 | β-=100%; β-n ?; β-2n ? |
| 110Zr | 109.954675 ± 0.000537 [Estimated] | 37.5 ms ± 2.0 | 1997 | β-=100%; β-n ?; β-2n ? |
| 111Zr | 110.960837 ± 0.000644 [Estimated] | 24.0 ms ± 0.5 | 2010 | β-=100%; β-n ?; β-2n ? |
| 112Zr | 111.965196 ± 0.000751 [Estimated] | 43 ms ± 21 | 2010 | β-=100%; β-n ?; β-2n ? |
| 113Zr | 112.971723 ± 0.000322 [Estimated] | 15 ms >550 n [Estimated] | 2018 | β- ?; β-n ?; β-2n ? |
