Argon

18
Ar
Skupina
18
Perioda
3
Blok
p
Protons
Electrons
Neutrons
18
18
22
General Properties
Vrstno število
18
Atomska teža
39,948
Mass Number
40
Kategorija
Žlahtni plini
Barva
Brezbarven
Radioactive
Ne
From the Greek argos, inactive
Kristalna struktura
Ploskovno centrirana kubična
Zgodovina
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.
Electrons per shell
2, 8, 8
Razporeditev elektronov
[Ne] 3s2 3p6
Ar
Argon makes a distinctive blue-green gas laser
Physical Properties
Faza snovi
Plin
Gostota
0,0017837 g/cm3
Tališče
83,8 K | -189,35 °C | -308,83 °F
Vrelišče
87,3 K | -185,85 °C | -302,53 °F
Talilna toplota
1,18 kJ/mol
Izparilna toplota
6,5 kJ/mol
Toplotna kapaciteta
0,52 J/g·K
Abundance in Earth's crust
0,00015%
Abundance in Universe
0,02%
Vial
Zasluge za slike: Images-of-elements
Vial of glowing ultrapure argon
CAS Number
7440-37-1
PubChem CID Number
23968
Atomic Properties
Atomski polmer
71 pm
Kovalentni polmer
106 pm
Elektronegativnost
-
Ionization Potential
15,7596 eV
Atomic Volume
22,4 cm3/mol
Toplotna prevodnost
0,0001772 W/cm·K
Oksidacijska stanja
0
Applications
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
Isotopes
Stable Isotopes
36Ar, 38Ar, 40Ar
Unstable Isotopes
30Ar, 31Ar, 32Ar, 33Ar, 34Ar, 35Ar, 37Ar, 39Ar, 41Ar, 42Ar, 43Ar, 44Ar, 45Ar, 46Ar, 47Ar, 48Ar, 49Ar, 50Ar, 51Ar, 52Ar, 53Ar