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THE ELEMENTS OF STRONTIUM

THE ELEMENTS OF STRONTIUM





ALKALINE EARTH METAL

Atomic number:38

Group numbers:2

Period:5

Electronic configuration:[Kr]5s2

Formal oxidation number:+2

Electronegativities:0.95

Atomic radius / pm:215.1

Relative atomic mass:87.62 ± 0.01

 

Strontium was discovered byAdairCrawford(GB)in1789. Named after the village ofStrontianinScotland.Itis a soft, malleable, silvery-yellowmetal thatiscombustibleinair and reacts with water. Exposedsurfacesformprotectiveoxidefilm. It ignites and burns readily.Strontiumisfound inmineralscelestite and strontianite. Strontium isusedinflaresandfireworks for crimson colour. Strontium-90 isalonglivedhighlyradioactive fallout product ofatomic-bombexplosions.

CRYSTALLOGRAPHIC DATA
face-centered cubic

Crystal structure:

face-centered cubic

Unit-cell dimensions / pm:

a=608.49

Space group:

Fm3m

 
PHYSICAL PROPERTIES

Density / g dm-3:2540(293 K)

 2375 (m.p.)

Molar volume / cm3mol-1:34.50 (293 K)

 36.89 (m.p.)

Electrical resistivity / μΩcm:23(20 °C)

THERMAL PROPERTIES

Thermal conductivity / Wm-1K-1:49

Melting point / °C:777

Boiling point / °C:1382

Heat of fusion / kJ mol-1:9.16

Heat of vaporization / kJ mol-1:154.4

Heat of atomization / kJ mol-1:164.4

IONIZATION ENERGIES

1st ionization energy / kJ mol-1:549.48

2nd ionization energy / kJ mol-1:1064.25

3rd ionization energy / kJ mol-1:4138.29

ABUNDANCE OF ELEMENTS

in the atmosphere / ppm:-

in the Earth's crust / ppm:260

in the oceans / ppm:8

ISOTOPES
IsotopeRelativeatomicmassMasspercent(%)
84Sr83.913425(4)0.56(1)
86Sr85.909262(2)9.86(1)
87Sr86.908879(2)7.00(1)
88Sr87.905614(2)82.58(1)
REDUCTION POTENTIALS
Balanced half-reaction Eo / V
Sr2+ + 2e- = Sr(s)- 2.89

 

37Rubidium <= 38Strontium =>39Yttrium 
 
Posted by Periodni







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