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Ar

Argon

Atomic number: 18Mass: 39.948 uCategory: Noble Gas

About Argon

Argon is the third most abundant gas in the Earth's atmosphere. It is inert, colourless, and odourless. Because it is completely chemically inert, it is used to protect reactive materials from oxygen and moisture.

Properties

Period
3
Group
18
Block
P
Category
Noble Gas
Electronegativity
N/A
Ionization Energy
1520.6 kJ/mol
Melting Point
84 K (-189°C)
Boiling Point
87 K (-186°C)
Density
1.784 g/L
Oxidation States
None

Electron Configuration

1s² 2s² 2p⁶ 3s² 3p⁶
[Ne] 3s² 3p⁶
Shell 1:2e⁻
Shell 2:8e⁻
Shell 3:8e⁻

Real-World Uses

Welding shield gas
Light bulbs
Double-glazed windows
Wine preservation
Laser technology

Fun Fact

About 1% of every breath you take is argon — and you breathe it out completely unchanged because it doesn't react with anything in your body.