Question

Question 17 Put tick () against correct choice and cross () against wrong choice in the following question: Number of valence electrons in Cl − ion are: (a) 16 (b) 8 (c) 17 (d) 18

Class 9 - Science - Structure of the Atom Page 55

Answer 1

Hey there


Question 17) Number of valence electrons in Cl − ion are:


First of all Cl is Chlorine with atomic number = 17.


It's electronic configuration is as follows:

2,8,7.

So, the number of electrons in valence shell that is the outermost shell = 7.

And in this case, Cl gain 1 electron to become an ion ( Cl -). Thus, 7+1 = 8 at the valence shell.


∴ option b) 8 is the correct answer!



Hope dis helps 

Answer 2

Explanation:

refer the attachment..