Question

How can valency of an element be determined if its electronic configuration is not what will be the valency of an element of atomic number 9?

Answer 1

Answer:

valecy can  be determined by looking at the number of electrons in outermost shell, if the number exceeds 4 then the valency is given by subtracting the number of electrons from 8 . since atomic number is 9 its electronic configuration will be 2,7 , so its valency = 8-7 which is 1. so valency of the element with atomic number 9 is 1