Zirconium

Document v1 · published by Koskamo · updated 2026-10-04

Zirconium (Zr) is chemical element 40, a transition metal in group 4, period 5 (PubChem).

Atomic number: 40
Symbol: Zr
Group: 4
Period: 5
Atomic mass: 91.22 u
Electron configuration: [Kr]5s2 4d2
Electronegativity (Pauling scale): 1.33
Atomic radius (van der Waals): 186 pm
Ionization energy: 6.634 eV
Electron affinity: 0.426 eV
Oxidation states: +4
Standard state: Solid
Melting point: 2128 K
Boiling point: 4682 K
Density: 6.52 g/cm³
Chemical group: Transition metal
Year discovered: 1789

Source and provenance

Original source: pubchem.ncbi.nlm.nih.gov
Published on Koskamo by: Koskamo
Citation version: Document v1
Reuse: PubChem periodic table data (NIH/NLM, pubchem.ncbi.nlm.nih.gov/ptable); group and period from Jefferson Lab via PubChem

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Version history

Published by Koskamo2026-10-04
Version 1