Chemical element【氩】,yà,Ar,Argon - Periodic Table

yà
氩
18
Ar
Noble gases
Argon

Group
18
Period
3
Block
p

Chemical element【氩】

Protons
18
Electrons
18
Neutrons
22

希腊文“惰性”

General Properties

Atomic Number: 18
Atomic Weight: 39.948
Mass Number: 40
Category: Noble gases
Color: Colorless
Radioactive: No
Discovery year: 1894

Crystal Structure: Face Centered Cubic

History

氩被亨利卡文迪许怀疑存在是在1785年

但是知道1894年才被劳德瑞林和威廉拉姆齐在苏格兰分离出来

氩是稀有气体的第一位会员

1957年，国际纯粹与应用化学协会同意了把其元素符号由A改为Ar

Electrons per shell: 2, 8, 8
Electron Configuration: [Ne] 3s² 3p⁶

Physical Properties

Phase: Gas
Density: 0.0017837g/cm³
Melting Point: 83.8 K | -189.35 °C | -308.83 °F
Boiling Point: 87.3 K | -185.85 °C | -302.53 °F
Heat of Fusion: 1.18 kJ/mol
Heat of Vaporization: 6.5 kJ/mol
Specific Heat Capacity: 0.52 J/g·K

Atomic Properties

Atomic Radius: 71 pm
Covalent Radius: 106 pm
Electronegativity: -
Ionization Potential: 15.7596 eV
Atomic Volume: 22.4 cm³/mol
Thermal Conductivity: 0.0001772 W/cm·K
Oxidation States: 0

Abundance in Earth's crust: 0.00015%
Abundance in Universe: 0.02%

CAS Number: 7440-37-1
PubChem CID Number: 23968

Applications

氩气被用来填充白炽灯和荧光灯

氩同样可以用作弧焊和弧切割的保护气氛

同样的可以用作生产硅，锗，钛的保护气氛

氩会产生独特的蓝绿色气体激光

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