Argon

18
Ar
Gruppe
18
Periode
3
Blok
p
Protoner
Elektroner
Neutroner
18
18
22
Generelle Egenskaber
Atomnummer
18
Atommasse
39,948
Masseantal
40
Kategori
Ædelgasser
Farve
Farveløs
Radioaktiv
Nej
From the Greek argos, inactive
Krystalstruktur
Fladecentreret Kubisk
Historie
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.
Elektroner i hver skal
2, 8, 8
Elektronkonfiguration
[Ne] 3s2 3p6
Ar
Argon makes a distinctive blue-green gas laser
Fysiske Egenskaber
Tilstandsform
Gas
Massefylde
0,0017837 g/cm3
Smeltepunkt
83,8 K | -189,35 °C | -308,83 °F
Kogepunkt
87,3 K | -185,85 °C | -302,53 °F
Smeltevarme
1,18 kJ/mol
Fordampningsvarme
6,5 kJ/mol
Varmefylde
0,52 J/g·K
Forekomst i jordskorpen
0,00015%
Forekomst i universet
0,02%
Vial
Billede akkrediteringer: Images-of-elements
Vial of glowing ultrapure argon
CAS-nummer
7440-37-1
PubChem CID-nummer
23968
Atomare egenskaber
Atomradius
71 pm
Kovalent radius
106 pm
Elektronegativitet
-
Ioniseringspotentiale
15,7596 eV
Atomvolumen
22,4 cm3/mol
Varmeledningsevne
0,0001772 W/cm·K
Oxidationstrin
0
Anvendelser
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
Isotoper
Stabile isotoper
36Ar, 38Ar, 40Ar
Ustabile isotoper
30Ar, 31Ar, 32Ar, 33Ar, 34Ar, 35Ar, 37Ar, 39Ar, 41Ar, 42Ar, 43Ar, 44Ar, 45Ar, 46Ar, 47Ar, 48Ar, 49Ar, 50Ar, 51Ar, 52Ar, 53Ar