Why is the group to which the noble gases belong termed as zero group?

Explanation

Due to very stable closed shell electronic configuration (`1s^(2)` in He and `ns^(2)np^(6)` or octet in other members), the noble gases generally do not take part in chemical reactions. Since, they do not have any tendency to either gain or lose electrons, the noble gases show zero valency due to chemical inertness. On account of zero valency, the group to which these elements belong is termed as zero group.