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.

Crystal structure:

face-centered cubic

Unit-cell dimensions / pm:

a=608.49

Space group:

Fm3m

 

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 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

1st ionization energy / kJ mol^-1:549.48

2nd ionization energy / kJ mol^-1:1064.25

3rd ionization energy / kJ mol^-1:4138.29

in the atmosphere / ppm:-

in the Earth's crust / ppm:260

in the oceans / ppm:8

Sr²⁺ + 2e^- Sr(s)- 2.89

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







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