Zirconium

Transition metal · 91.22 u · group 4, period 5

Zirconium · Zr

Atomic number40

SymbolZr

CategoryTransition metal

Standard stateSolid

Group · Period · Block4 · 5 · d

Electron configuration[Kr]5s2 4d2

Atomic mass91.22 u

Atomic radius186 pm

Protons / Neutrons / Electrons40 / 51 / 40

Shells (e⁻ per shell)2, 8, 18, 10, 2

Electronegativity (Pauling)1.33

Ionization energy6.634 eV

Electron affinity0.426 eV

Oxidation states+4

Melting point2.13e+3 K · 1.85e+3 °C

Boiling point4.68e+3 K · 4.41e+3 °C

Density6.52 g/cm³

Year discovered1789

CPK color

#94E0E0

State at room temp (25 °C)

solid

Position