Argon
Argon (Ar) is a chemical element belonging to the category Noble gas, with atomic number 18 and standard atomic mass 39.9480 u. This sheet describes its fundamental properties, periodic position and physical characteristics.
Identity
- Name: Argon
- Symbol: Ar
- Atomic number: 18
- Atomic mass: 39.9480 u
Position in the periodic table
- Group: 18
- Period: 3
- Category: Noble gas
Physico-chemical properties
- Standard state: Gas
- Melting point: −189.3 °C
- Boiling point: −185.8 °C
- Density (gas, 0 °C, 1 atm): 0.001784 g/cm³
- Electron configuration: [Ne] 3s² 3p⁶
Scientific description
Argon is a colorless, odourless noble gas with symbol Ar and atomic number 18. It occupies group 18 and period 3 of the periodic table and is chemically very inert under standard conditions. Its standard atomic mass is 39.9480 u, and it is the third most abundant gas in the Earth's atmosphere.
KODO: H9