18Ar
Element 18
Argon
Noble gases
Argon is a chemical element with symbol Ar and atomic number 18.
Key data
- Atomic number
- 18
- Atomic mass
- 39.948 u
- Group / Period
- 18 / 3
- Block
- p-block
- Phase at STP
- Gas
- Density
- 1.784 g/cm³
- Melting point
- -189.3 °C
- Boiling point
- -185.8 °C
- Electron configuration
- [Ne] 3s2 3p6
Common uses
- •Welding shield
- •Insulating windows
- •Light bulb fill
Discovery
Year: 1894
Discovered by: Lord Rayleigh
Frequently asked questions
What is the atomic number of Argon?
Argon has atomic number 18. Its symbol is Ar and its atomic mass is 39.948 u.
What category of element is Argon?
Argon is classified as noble gases. It sits in group 18, period 3 of the periodic table.
What is Argon used for?
Common uses of Argon include: Welding shield, Insulating windows, Light bulb fill.
When was Argon discovered?
Argon was discovered in 1894 by Lord Rayleigh.
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