Strontium

38
Sr
Gruppe
2
Periode
5
Blokk
s
Protoner
Elektroner
Nøytroner
38
38
50
Generelle egenskaper
Atomnummer
38
Atomvekt
87,62
Massetall
88
Kategori
Jordalkalimetaller
Farge
Sølv
Radioaktiv
Nei
Named after Strontian, a town in Scotland
Krystallstruktur
Face Centered Cubic
Historie
Strontium was recognized as a new element in 1790 when Adair Crawford and his colleague William Cruickshank analyzed a mineral sample from a lead mine near Strontian, Scotland.

The element was eventually isolated by Sir Humphry Davy in 1808.

The isolation was done by the electrolysis of a mixture containing strontium chloride and mercuric oxide.
Elektroner per energinivå
2, 8, 18, 8, 2
Elektronkonfigurasjon
[Kr] 5s2
Sr
Strontium metal turns yellow when exposed to air
Fysikalske egenskaper
Fase
Fast stoff
Tetthet
2,64 g/cm3
Smeltepunkt
1050,15 K | 777 °C | 1430,6 °F
Kokepunkt
1655,15 K | 1382 °C | 2519,6 °F
Smeltevarme
8 kJ/mol
Fordampningsvarme
137 kJ/mol
Spesifikk varmekapasitet
0,301 J/g·K
Forekomst i jordskorpa
0,036%
Forekomst i universet
4×10-6%
The
Bildekreditter: Wikimedia Commons (Alchemist-hp)
The chemical element strontium as a synthetic made crystals, sealed under argon in a glas ampoule
CAS Number
7440-24-6
PubChem CID Number
5359327
Atomegenskaper
Atomradius
215 pm
Kovalent radius
195 pm
Elektronegativitet
0,95 (Pauling-skalaen)
Ioniseringsenergi
5,6949 eV
Molart volum
33,7 cm3/mol
Termisk ledningsevne
0,353 W/cm·K
Oksidasjonstilstander
1, 2
Bruksområder
The primary use for strontium is in glass for color television cathode ray tubes.

Strontium salts are used in flares and fireworks for a crimson color.

Strontium chloride is used in toothpaste for sensitive teeth.

Strontium oxide is used to improve the quality of pottery glazes.
Strontium's non-radioactive isotopes are considered non-toxic
Isotoper
Stabile isotoper
84Sr, 86Sr, 87Sr, 88Sr
Ustabile isotoper
73Sr, 74Sr, 75Sr, 76Sr, 77Sr, 78Sr, 79Sr, 80Sr, 81Sr, 82Sr, 83Sr, 85Sr, 89Sr, 90Sr, 91Sr, 92Sr, 93Sr, 94Sr, 95Sr, 96Sr, 97Sr, 98Sr, 99Sr, 100Sr, 101Sr, 102Sr, 103Sr, 104Sr, 105Sr