Zirconium (Zr)
Transition metal · d-block · period 5 · group 4
Hard, lustrous, greyish-white metal.
Zirconium (symbol Zr) is chemical element number 40, a transition metal in group 4, period 5 of the periodic table. Its standard atomic weight is 91.224 and its electron configuration is [Kr] 4d2 5s2. At room temperature it is a solid. Barely absorbs neutrons, so it sheathes the fuel rods in almost every nuclear reactor.
Properties
| Atomic number | 40 |
|---|---|
| Atomic mass | 91.224 |
| Category | Transition metal |
| Block | d-block |
| Group · Period | 4 · 5 |
| Electron configuration | [Kr] 4d2 5s2 |
| Electrons per shell | 2, 8, 18, 10, 2 |
| State at 25 °C | solid |
| Melting point | 2128 K |
| Boiling point | 4650 K |
| Density | 6.52 g/cm³ |
| Electronegativity (Pauling) | 1.33 |
| Radioactive | No |
| Origin | primordial |
| Discovered | 1789 · Martin Heinrich Klaproth |
Key facts about Zirconium
- Barely absorbs neutrons, so it sheathes the fuel rods in almost every nuclear reactor.
- Extremely resistant to corrosion by acids, alkalis and seawater.
- Cubic zirconia is a cheap, brilliant diamond substitute.
- Its name comes from the Persian for 'gold-coloured', after the gem zircon.
What Zirconium is used for
Nuclear fuel cladding, corrosion-resistant chemical plant, cubic zirconia gems, foundry moulds, ceramics.
Where it sits in the periodic table
Zirconium is in group 4, period 5, of the d-block. Its electron configuration [Kr] 4d2 5s2 means its outermost shell holds 2 electrons, which is what places it here and explains much of its chemistry. See Zirconium on the interactive table →
Zirconium — frequently asked questions
What is Zirconium used for?
Nuclear fuel cladding, corrosion-resistant chemical plant, cubic zirconia gems, foundry moulds, ceramics.
Is Zirconium radioactive?
No. Zirconium has at least one stable isotope and is not radioactive.
What is the electron configuration of Zirconium?
Zirconium has the electron configuration [Kr] 4d2 5s2, which is 2, 8, 18, 10, 2 electrons per shell.
What group and period is Zirconium in?
Zirconium is in group 4, period 5, in the d-block. Its outer shell holds 2 electrons.
Who discovered Zirconium?
Zirconium was discovered in 1789 by Martin Heinrich Klaproth.