Argon Gas - Ar

What is Argon Gas?

Argon is the first noble gas to be discovered. It was identified by English physicist Lord Rayleigh and Scottish chemist William Rammsay in 1894. Argon is from the Greek word “argos” which means “lazy” or “inactive”. It belongs to noble gas and makes up about 0.93% of Earth’s atmosphere. It is the third most abundant gas in the atmosphere. Non flammable cryogenics gases are sometimes referred to as inert gases.




1.784 g/L

Molecular Weight/ Molar Mass

39.948 u

Boiling Point

-185.8 °C

Melting Point

-189.4 °C

Chemical Formula


Argon Gas Structure – Ar

Physical Properties of Argon Gas – Ar




Colorless gas

Period (periodic table)

period 3

Block (periodic table)


Atomic number (Z)


Element category

Noble gas

Solubility in water

62 mg/L at 20oC and 1 bar pressure

Chemical Properties of Argon Gas - Ar

Argon is a noble gas that is chemically inert but at low temperature it is possible to combine with other atoms to form a very fragile compounds which exist at very low temperatures. Since this element do not exhibit any chemical reactivity it is called noble gas.

Uses of Argon Gas – Ar

  • Argon-enhanced electrosurgery uses argon gas to increase the effectiveness of the ESU, resulting in less tissue damage and less blood loss.

  • Argon plasma coagulation uses electricity conductive argon plasma as a medium to deliver a high frequency current to coagulate tissue. The non-contact feature permits rapid coagulation with minimal manipulation and trauma to the target tissue.

  • In electric lamp industry argon is used as the standard filling for incandescent filament lamps and neon discharge tubes being familiar in advertising signs.