Respuesta :

jacksonlucas2004

Answer:

Helium neon and Argon are called inert gases are noble gas because they have complete its duplet as well as Octate. and no other element like Helium neon and Argon complete its octate and duplete. in the 18th period all element are inert. Which gas does not exist in air?

Explanation:

xxxVikrantxxx

Answer:

The outermost (valence) shell of argon has eight electrons, making it exceedingly stable and, thus, chemically inert.