Strontium, 38Sr
Strontium
Pronunciation
Appearancesilvery white metallic; with a pale yellow tint[1]
Standard atomic weight Ar°(Sr)
Strontium in the periodic table
Atomic number (Z)38
Groupgroup 2 (alkaline earth metals)
Periodperiod 5
Block  s-block
Electron configuration[Kr] 5s2
Electrons per shell2, 8, 18, 8, 2[4]
Physical properties
Phase at STPsolid
Melting point1050 K (777 °C, 1431 °F)
Boiling point1650 K (1377 °C, 2511 °F)
Density (at 20° C)2.582 g/cm3[5]
when liquid (at m.p.)2.375 g/cm3
Heat of fusion7.43 kJ/mol
Heat of vaporization141 kJ/mol
Molar heat capacity26.4 J/(mol·K)
Specific heat capacity301.301 J/(kg·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 796 882 990 1139 1345 1646
Atomic properties
Oxidation statescommon: +2
+1[6]
ElectronegativityPauling scale: 0.95
Ionization energies
  • 1st: 549.5 kJ/mol
  • 2nd: 1064.2 kJ/mol
  • 3rd: 4138 kJ/mol
Atomic radiusempirical: 215 pm
Covalent radius195±10 pm
Van der Waals radius249 pm
Color lines in a spectral range
Spectral lines of strontium
Other properties
Natural occurrenceprimordial
Crystal structure face-centered cubic (fcc) (cF4)
Lattice constant
Face-centered cubic crystal structure for strontium
a = 608.6 pm (at 20 °C)[5]
Thermal expansion22.55×10−6/K (at 20 °C)[5]
Thermal conductivity35.4 W/(m⋅K)
Electrical resistivity132 nΩ⋅m (at 20 °C)
Magnetic orderingparamagnetic
Molar magnetic susceptibility−92.0×10−6 cm3/mol (298 K)[7]
Young's modulus15.7 GPa
Shear modulus6.03 GPa
Poisson ratio0.28
Mohs hardness1.5
CAS Number7440-24-6
History
Namingafter the mineral strontianite, itself named after Strontian, Scotland
DiscoveryWilliam Cruickshank (1787)
First isolationHumphry Davy (1808)
Isotopes of strontium
Main isotopes[8] Decay
Isotope abun­dance half-life (t1/2) mode pro­duct
82Sr synth 25.35 d ε 82Rb
83Sr synth 32.41 h β+ 83Rb
84Sr 0.56% stable
85Sr synth 64.846 d ε 85Rb
86Sr 9.86% stable
87Sr 7% stable
88Sr 82.6% stable
89Sr synth 50.56 d β 89Y
90Sr trace 28.91 y β 90Y
 Category: Strontium
| references
child table, as reused in {IB-Sr}
Main isotopes of strontium
Main isotopes[8] Decay
Isotope abun­dance half-life (t1/2) mode pro­duct
82Sr synth 25.35 d ε 82Rb
83Sr synth 32.41 h β+ 83Rb
84Sr 0.56% stable
85Sr synth 64.846 d ε 85Rb
86Sr 9.86% stable
87Sr 7% stable
88Sr 82.6% stable
89Sr synth 50.56 d β 89Y
90Sr trace 28.91 y β 90Y
Data sets read by {{Infobox element}}
Name and identifiers
Symbol etymology (11 non-trivial)
Top image (caption, alt) caption:
alt:
Pronunciation
Allotropes (overview)
Group (overview)
Period (overview)
Block (overview)
Natural occurrence
Phase at STP
Oxidation states
Spectral lines image
Electron configuration (cmt, ref)
Isotopes
Standard atomic weight
  most stable isotope
Wikidata
Wikidata *
* Not used in {{Infobox element}} (2023-01-01)
See also {{Index of data sets}} · Cat:data sets (45) · (this table: )

References

  1. Greenwood and Earnshaw, p. 112
  2. "Standard Atomic Weights: Strontium". CIAAW. 1969.
  3. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
  4. "Periodic Table of Elements: Strontium - Sr (EnvironmentalChemistry.com)". environmentalchemistry.com. Retrieved 7 December 2022.
  5. 1 2 3 Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.
  6. Colarusso, P.; Guo, B.; Zhang, K.-Q.; Bernath, P. F. (1996). "High-Resolution Infrared Emission Spectrum of Strontium Monofluoride" (PDF). J. Molecular Spectroscopy. 175 (1): 158. Bibcode:1996JMoSp.175..158C. doi:10.1006/jmsp.1996.0019.
  7. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
  8. 1 2 Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3) 030001. doi:10.1088/1674-1137/abddae.