Question

Derive the valency of the elements with atomic numbers 10 and 12

Answer 1

valency of elements is combining capacity
10- it's electronic configuration would be 2,8
so it's valency is 0
and it should be because it's a noble gas neon
12- it's electronic configuration would be 2,8,2
so it's valency is 2

Answer 2

First of all,
Valency refers to the no. of electrons in the outermost shell that can be given out, shared or taken by an atom.

• the one with the no of electrons as 10
Distribution of electrons in each shell or electronic configuration:-
K Shell - 2
L shell - 8
so, as the outermost shell doesn't have any electron to be taken, given out or shared so it's valency is 0
This element can be of Neon coz it's atomic no. is 10
• Second element with no. Of electrons as 10
Electronic configuration
K shell - 2
L Shell - 8
M shell - 2
here M shell is outer most shell and it has 2 electrons that can be given out or shared, so it's valency is 2
This element can be of Magnesium as it's atomic no. is 12

Hope it helps....