How to find VALENCY of ARGON ?
This video tells about what is valency and how to find it from atomic number.
Valency is the combining capacity of an element. Atoms combine with other atom by sharing, gaining or losing electrons to get octet configuration( 8 valence electrons)
For atoms having more than 4 valence electrons losing electrons is hard, they preferred to gain electrons. In such cases we need to subtract (octet) 8 from valence electrons.
Argon , atomic number 18
Its electronic configuration is 2,8,8
Since there are 8 valence electrons, we should subtract 8 from octet(8)
8-8=0
valency of Argon is 0.That is why it stays as an inert gas.