The chemical symbol for Strontium is Sr and its atomic number is 38.
We find it listed in the periodic table of elements in group 2 and 5 and block period s.
Strontium belongs to the family of alkaline earth metals such as for example Barium, Beryllium, Calcium ...
This element is stable.
Strontium came from the name of the town Strontian a place where Sr was discovered for the first time.
Atomic number (Z) 38
Group, block group 2 (alkaline earth metals), s-block
Period: period 5
Element category: alkaline earth metal
Standard atomic weight (±) (Ar): 87.62(1)[2]
Electron configuration: [Kr] 5s2
per shell: 2, 8, 18, 8, 2
Physical properties
Phase: solid
Melting point: 1050 K (777 °C, 1431 °F)
Boiling point: 1650 K (1377 °C, 2511 °F)
Density near r.t.: 2.64 g/cm3
when liquid, at m.p. 2.375 g/cm3
Heat of fusion: 7.43 kJ/mol
Heat of vaporization: 141 kJ/mol
Molar heat capacity: 26.4 J/(mol•K)
Atomic properties
Oxidation states: 2, 1 (a strongly basic oxide)
Electronegativity: Pauling scale: 0.95
Ionization energies 1st: 549.5 kJ/mol
2nd: 1064.2 kJ/mol
3rd: 4138 kJ/mol
Atomic radius empirical: 215 pm
Covalent radius: 195±10 pm
Van der Waals radius: 249 pm
Crystal structure: face-centered cubic
Thermal expansion 22.5 µm/(m•K) (at 25 °C)
Thermal conductivity: 35.4 W/(m•K)
Electrical resistivity: 132 nΩ•m (at 20 °C)
Magnetic ordering paramagnetic
Young's modulus: 15.7 GPa
Shear modulus : 6.03 GPa
Poisson ratio: 0.28
Mohs hardness: 1.5
CAS Number: 7440-24-6