Stable isotope Strontium (Sr)

Isotope Z(p) N(n) Atomic Mass Natural Abundance Enrichment Level Chemical Form
Sr-84 38 46 83.913426 0.56% 68.70-82.00% Carbonate
Sr-86 38 48 85.909265 9.86% >96.00% Carbonate
Sr-87 38 49 86.908882 7.00% >90.00% Carbonate
Sr-88 38 50 87.905617 82.58% 99.90% Carbonate

Properties of Strontium

Name Strontium
Symbol Sr
Atomic number 38
Atomic weight 87.62
Standard state Solid at 298 °K
CAS Registry ID 7440-24-6
Group in periodic table 2
Group name Alkaline earth metal
Period in periodic table 5
Block in periodic table s-block
Color Silvery white
Classification Metallic
Melting point 777 °C
Boiling point 1384 °C
Vaporization point 1382 °C
Thermal conductivity 35.4 W/(m·K) at 298.2 °K
Electrical resistivity 23.0 µΩ·cm at 20 °C
Electronegativity 1.0
Specific heat 0.3 kJ/kg K
Heat of vaporization 137 kJ·mol-1
Heat of fusion 8 kJ·mol-1
Density of liquid 2.38 g/cm3 at 777 °C
Density of solid 2.64 g/cm3
Electron configuration [Kr]5s
Atomic radius 2.15 Å
Oxidation state +2
Ionic radius Sr2+: 1.26 Å and 1.44 Å (coordination numbers 8 and 12, respectively)