Argon

18
Ar
Grupp
18
Period
3
Block
p
Protoner
Elektroner
Neutroner
18
18
22
Generella Egenskaper
Atomnummer
18
Atommassa
39,948
Masstal
40
Kategori
Ädelgaser
Färg
Färglös
Radioaktiv
Nej
From the Greek argos, inactive
Kristallstruktur
Ytcentrerat kubiskt
Historia
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 per skal
2, 8, 8
Elektronkonfiguration
[Ne] 3s2 3p6
Ar
Argon makes a distinctive blue-green gas laser
Fysikaliska Egenskaper
Aggregationstillstånd
Gasformig
Densitet
0,0017837 g/cm3
Smältpunkt
83,8 K | -189,35 °C | -308,83 °F
Kokpunkt
87,3 K | -185,85 °C | -302,53 °F
Smältvärme
1,18 kJ/mol
Ångbildningsvärme
6,5 kJ/mol
Specifik värmekapacitet
0,52 J/g·K
Abundance in Earth's crust
0,00015%
Abundance in Universe
0,02%
Vial
Bildkrediter: Images-of-elements
Vial of glowing ultrapure argon
CAS Number
7440-37-1
PubChem CID Number
23968
Atomära Egenskaper
Atomradie
71 pm
Kovalent radie
106 pm
Elektronegativitet
-
Jonisationspotential
15,7596 eV
Molvolym
22,4 cm3/mol
Värmeledningsförmåga
0,0001772 W/cm·K
Oxidationstillstånd
0
Användningsområden
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
Stabila isotoper
36Ar, 38Ar, 40Ar
Instabila isotoper
30Ar, 31Ar, 32Ar, 33Ar, 34Ar, 35Ar, 37Ar, 39Ar, 41Ar, 42Ar, 43Ar, 44Ar, 45Ar, 46Ar, 47Ar, 48Ar, 49Ar, 50Ar, 51Ar, 52Ar, 53Ar