Question

(a) What is the usual number of valence electrons and valency of group 18 elements of the periodic table?
(b) What happens to the number of valence electrons in the atoms of elements as we go down in a group of the periodic table?

Answer 1

(a) The usual number of valence electrons of group 18 elements is 8. Therefore, the valency of the group 18 elements is: 8-8=0.

(b) On moving down in a group of the periodic table, the number of valence electrons in the atoms of elements remains the same.