Zirconium

Koushik 26/06/2026 19:58:08 Updated 26/06/2026 19:58:08

Property	Value
Atomic Number	40
Element	Zirconium
Symbol	Zr
Atomic Mass	91.224 u
Number of Neutrons	51 (most common isotope, Zirconium-90)
Number of Protons	40
Number of Electrons	40
Period	5
Group	4
Phase	Solid
Radioactive	No
Natural	Yes
Metal	Yes
Nonmetal	No
Metalloid	No
Type	Transition Metal
Atomic Radius	206 pm
Electronegativity	1.33 (Pauling scale)
First Ionization Energy	6.634 eV
Density	6.52 g/cm³
Melting Point	1855 °C
Boiling Point	4409 °C
Number of Isotopes	5 naturally occurring (Zr-90, Zr-91, Zr-92, Zr-94, Zr-96)
Discoverer	Martin Heinrich Klaproth
Year	1789
Specific Heat	0.278 J/g·K
Number of Shells	5
Number of Valence Electrons	4