Strontium
Strontium General
| Name:Strontium | Symbol:Sr |
| Type:Alkali Earth Metal | Atomic weight:87.62 |
| Density @ 293 K:2.6 g/cm3 | Atomic volume:33.7 cm3/mol |
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Discovered:
Strontium was recognized as distinct from barium in 1790 by Adair Crawford in a mineral sample from a mine near Strontian, Scotland. The element took its name from the Scottish town. The metal was first isolated by Sir Humphry Davy in 1808, by electrolysis. |
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Strontium States
| State (s, l, g):solid | |
| Melting point:1050 K (777 °C) | Boiling point:1653 K (1380 °C) |
Strontium Energies
| Specific heat capacity: 0.30 J g-1 K-1 | Heat of atomization:164 kJ mol-1 |
| Heat of fusion:8.30 kJ mol-1 | Heat of vaporization :144.0 kJ mol-1 |
| 1st ionization energy:549.5 kJ mol-1 | 2nd ionization energy:1064.2 kJ mol-1 |
| 3rd ionization energy:4138 kJ mol-1 | Electron affinity:5 kJ mol-1 |
Strontium Oxidation & Electrons
| Shells:2,8,18,8,2 | Electron configuration: [Kr] 5s2 |
| Minimum oxidation number: 0 | Maximum oxidation number:2 |
| Min. common oxidation no.: 0 | Max. common oxidation no.:2 |
| Electronegativity (Pauling Scale):0.95 | Polarizability volume:27.6 Å3 |
Strontium Appearance & Characteristics
| Structure:ccp: cubic close-packed | Color: silvery |
| Hardness:1.5 mohs | |
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Harmful effects:
Strontium's non-radioactive isotopes are considered non-toxic. |
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Characteristics:
Strontium is a soft, silvery metal. When cut it quickly turns a yellowish color due to the formation of strontium oxide (strontia, SrO) . Finely powdered strontium metal is sufficiently reactive to ignite spontaneously in air. Uses: Strontium is used for producing glass (cathode ray tubes) for color televisions. It is also used in producing ferrite ceramic magnets and in refining zinc. |
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Strontium Reactions
| Reaction with air:vigorous, ⇒ SrO, Sr2N3 | Reaction with 6 M HCl:vigorous, ⇒ H2, SrCl2 |
| Reaction with 15 M HNO3:vigorous, ⇒ H2, Sr(NO3)2 | Reaction with 6 M NaOH:vigorous, ⇒ none |
Strontium Compounds
| Oxide(s):SrO, SrO2 (strontium peroxide) | Chloride(s):SrCl2 |
| Hydride(s):SrH2 |
Strontium Radius
| Atomic radius:215 pm | Ionic radius (1+ ion):pm |
| Ionic radius (2+ ion):132 pm | Ionic radius (3+ ion):pm |
| Ionic radius (2- ion):pm | Ionic radius (1- ion):pm |
Strontium Conductivity
| Thermal conductivity:35.4 W m-1 K-1 | Electrical conductivity:5 x 106 S m-1 |
Strontium Abundance & Isotopes
| Abundance earth's crust: 370 parts per million by weight, 87 parts per million by moles | |
| Abundance solar system: 50 parts per billion by weight, 0.7 parts per billion by moles | |
| Cost, pure:$100 per 100g | |
| Cost, bulk:$ per 100g | |
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Source:
Strontium is never found free in nature. The principal strontium ores are celestine (strontium sulfate, SrSO4) and strontianite (strontium carbonate, SrCO3). The main commercial process for strontium metal production is reduction of strontium oxide with aluminum. |
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Isotopes:
Strontium has 28 isotopes whose half-lives are known, with mass numbers 75 to 102. Of these, four are stable: 84Sr, 86Sr, 87Sr and 88Sr. 88Sr is the most abundant in nature at 82.6%. |
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Strontium Other
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Other:
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