Can u explain me how to count no of electrons in outermost shell in q. No. 5 ?

Dear student 

In such questions you have to count number of electrons in outermost shell.

Here there are two elements chlorine and oxygen.

You have to count the number of electrons in outermost shell and add them. If the count is odd number, it is odd electron species and if the count is even, it is even electron species.

Here ClO2

7 + 6*2 =19

WITH REGARDS 

MAHIMA 

ASKIITIANS FORUM EXPERT