Argon (Ar) — Element 18: Properties & Data | Aladdin Scientific
Argon(Ar) — Element 18
Argon (Ar) is a noble gas with atomic number 18 and atomic mass 39.9. It has melting point 83.8 K (-189 °C), boiling point 87.3 K (-186 °C), density 0.0017837 g/cm³. It sits in group 18 and period 3 of the periodic table and was discovered in 1894.
Key facts
| Atomic mass | 39.9000 u |
|---|---|
| Electron configuration | [Ne]3s2 3p6 |
| Atomic radius (van der Waals) | 188 pm |
| Ionization energy | 15.76 eV |
| Melting point | 83.8 K |
| Boiling point | 87.3 K |
| Density | 0.0017837 g/cm³ |
| Standard state | Gas |
| Year discovered | 1894 |
Frequently asked questions
What is the electron configuration of argon?
The ground-state electron configuration of argon is [Ne]3s2 3p6.
What group and period is argon in?
Argon (Ar) is in group 18 and period 3 of the periodic table, classified as a noble gas.
What is the melting point of argon?
Argon melts at 83.8 K (-189 °C).
What is the standard state of argon?
Argon is a gas at standard temperature and pressure.
Related elements
About this data: property values compiled from IUPAC Standard Atomic Weights (2021), the NIST Atomic Spectra Database, and PubChem. Curated by the Aladdin Scientific technical team. Last reviewed: .