Question

please answer how do we solve this

Answer 1

it's easy ....just count the electrons of each atom....and check the valance electron ....and you will get the ans.....and instead of counting all elements valancies just count the valance electron of the elements in option given

Answer 2

The shells drawn are the outermost shells u can now take out no of valence electrons and find out which element has the shown number of valence electrons

So y’s valence electrons are 6
And from the below options it can be understood that only oxygen is Y as it has 6 valence electrons
In case of z
It’s valence electrons are 7 and only sulphur has 7 valence electrons

Hope this helps