Argon

18
Ar
Gruppe
18
Periode
3
Block
p
Protonen
Elektronen
Neutronen
18
18
22
Generelle Eigenschaften
Ordnungszahl
18
Atommasse
39,948
Massenzahl
40
Kategorie
Edelgase
Farbe
Farblos
Radioaktiv
Nein
Aus dem Griechischen argos (inaktiv)
Kristallstruktur
Kubisch flächenzentriert
Geschichte
Argon was suspected to be present in air by Henry Cavendish in 1785.

It was not isolated until 1894 by Lord Rayleigh and Sir William Ramsay in Scotland.

Argon became the first member of the noble gases to be discovered.

In 1957, IUPAC agreed that the symbol should change from A to Ar.
Elektronen pro Schale
2, 8, 8
Elektronenkonfiguration
[Ne] 3s2 3p6
Ar
Argon makes a distinctive blue-green gas laser
Physikalische Eigenschaften
Aggregatzustand
Gasförmig
Dichte
0,0017837 g/cm3
Schmelzpunkt
83,8 K | -189,35 °C | -308,83 °F
Siedepunkt
87,3 K | -185,85 °C | -302,53 °F
Schmelzwärme
1,18 kJ/mol
Verdampfungswärme
6,5 kJ/mol
Spezifische Wärmekapazität
0,52 J/g·K
Häufigkeit in der Erdkruste
0,00015%
Häufigkeit im Universum
0,02%
Vial
Danksagungen für Bilder: Images-of-elements
Vial of glowing ultrapure argon
CAS-Nummer
7440-37-1
PubChem CID Number
23968
Atomeigenschaften
Atomradius
71 pm
Kovalenter Radius
106 pm
Elektronegativität
-
Ionisierungsenergie
15,7596 eV
Molares Volumen
22,4 cm3/mol
Wärmeleitfähigkeit
0,0001772 W/cm·K
Oxidationszustände
0
Anwendung
Argon gas is used to fill conventional incandescent and fluorescent light bulbs.

Argon is also used as an inert gas shield for arc welding and cutting, as blanket for the production of titanium and other reactive elements.

It is used as a protective atmosphere for growing silicon and germanium crystals.
Argon is considered to be non-toxic
Isotope
Stabile Isotope
36Ar, 38Ar, 40Ar
Instabile Isotope
30Ar, 31Ar, 32Ar, 33Ar, 34Ar, 35Ar, 37Ar, 39Ar, 41Ar, 42Ar, 43Ar, 44Ar, 45Ar, 46Ar, 47Ar, 48Ar, 49Ar, 50Ar, 51Ar, 52Ar, 53Ar