Zirconium
A corrosion-resistant metal used in nuclear reactor cladding.
Inside the Zirconium atom
Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Zirconium atom step by step.
Electron configuration
[Kr] 4d2 5s2
A neutral Zirconium atom has 40 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.
Shell distribution
Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.
Physical & atomic properties
- State (room temp)
- Solid
- Melting point
- 2128 K (1855 °C)
- Boiling point
- 4682 K (4409 °C)
- Density
- 6.506 g/cm³
- Electronegativity
- 1.33 Pauling
- Atomic radius
- 155 pm
- 1st ionization energy
- 640 kJ/mol
- Category
- Transition metals
Discovery & naming
- Discovered
- 1789
- Discovered by
- Martin Heinrich Klaproth
- Origin of name
- Arabic 'zargun', meaning gold-coloured.
Notable uses
Nuclear reactor cladding, ceramics, and abrasives.
Where Zirconium comes from
Stellar fusion and dying stars
Chiefly built by slow neutron capture in the interiors of dying low-mass stars.
Simplified origin map — many elements form through more than one astrophysical pathway.
Summary
- Atomic number
- 40
- Atomic mass
- 91.224
- Category
- Transition metals
- Group · Period
- 4 · 5
- Block
- d-block
- Shells
- 2 · 8 · 18 · 10 · 2