helium has ns^2 configuration and hence belongs to 18th group. why aren't the elements in group 2 considered as nobel?

Dear Student

 

Group 2 elements have also filled s orbital, but they have empty p-orbitals. while in Group 18 the elements have both s and p-filled orbitals.

In terms of elements Noble means non-reactive. Group 18 elements were found non-reactive so they were named as Noble. Group 2 elements are reactive metals, so we cant call them noble.

 

We hope that clarifies your query.

With regards,

Team

Topperlearning