Strontium

Symbol	Sr
Atomnummer	38
Gruppe	2 (Jordalkalimetaller)
Periode	5
Blok	s
Klassifikation	Jordalkalimetal

Udseende	-
Farve	Sølv

Antal protoner	38 p+
Antal neutroner	50 n0
Antal elektroner	38 e-

Fra Wikipedia, den gratis encyklopædiStrontium (efter mineralet strontianit, der igen er opkaldt efter den skotske by Strontian) er det 38. grundstof i det periodiske system, og har det kemiske symbol Sr. Under normale temperatur- og trykforhold fremtræder stoffet som et blødt, sølvhvidt metal, men da strontium ligesom de øvrige jordalkalimetaller er ganske reaktionsvilligt, angribes det af atmosfærisk luft og bliver derved gulligt. Strontium findes i mineralerne celestit og strontianit, og den radioaktive isotop strontium-90 indgår i det radioaktive nedfald fra atomvåben.

Fase ved STP	Fast
Massefylde	2.64 g/cm3
Atommasse	87.621 u

Smeltepunkt	1050 K 776.85 °C 1430.33 °F
Kogepunkt	1650 K 1376.85 °C 2510.33 °F
Fordampningsvarme	136.9 kJ/mol

Elektronegativitet (Pauling Scale)	0.95
Elektronaffinitet	5.023 kJ/mol
Oxidationstrin	+1, +2 (a strongly basic oxide)
Ioniseringsenergier	549.5 kJ/mol 1064.2 kJ/mol 4138 kJ/mol 5500 kJ/mol 6910 kJ/mol 8760 kJ/mol 10230 kJ/mol 11800 kJ/mol 15600 kJ/mol 17100 kJ/mol 31270 kJ/mol

Elektronkonfiguration Kortfattet konfiguration	[Kr] 5s2
Elektronkonfiguration Fuld konfiguration	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 5s2
Elektronkonfigurationsdiagram	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 5s2
Elektroner pr. Skal	2, 8, 18, 8, 2
Valenselektroner	2
Valency-elektroner	2
Bohrs atommodel	Figur: Skaldiagram af Strontium (Sr) atom.
Orbital diagram	1s 2s 2p 3s 3p 3d 4s 4p 5s

Opdaget	William Cruickshank (1787)
Første isolation	Humphry Davy (1808)
Navngivet af	Humphry Davy (1808)
Opdagelse af strontium Both strontium and strontianite are named after Strontian, a village in Scotland near which the mineral was discovered in 1790 by Adair Crawford and William Cruickshank; it was identified as a new element the next year from its crimson-red flame test color. The element was eventually isolated by Sir Humphry Davy in 1808 by the electrolysis of a mixture containing strontium chloride and mercuric oxide, and announced by him in a lecture to the Royal Society on 30 June 1808. In keeping with the naming of the other alkaline earths, he changed the name to strontium.

Original word	Strontian
Language of origin	English
Name source	Sted
Meaning	“Strontian village”
Land	United Kingdom
Naming The name is derived from Strontian, a small town in Scotland where the metal was first discovered in 1790.

CAS Number	7440-24-6
ChemSpider ID	4514263
EC number	231-133-4
PubChem CID Number	5359327