Question

why eigteenth group element are called 0 group​

Answer 1

Answer:

The elements in group 18 have octetrule , means their last cell is already filled and they have no valency that's why it iscalled zero group. The Valence shell of the elements of thisgroup is completely filled. ... They are non reactive - alsocalled as inert gas elements

Answer 2

Answer:

because 7 group is known as n. so 7 comes after 8 and ncomes befor o