Question

What is the relation between valency of an element and the no. of electrons present in outermost orbit of an element.

Answer 1

Valence and no. of electrons in outermost orbit is same kind of.

In sodium for ex
The presence of 8 electrons in theoutermost shell indicates stability of an atom. An atom tends to loseelectron if it has one to four electronsin its outermost orbit. When an atomdonates these free electrons it has positive valency.

Answer 2

The number of electrons in the outermost orbitnare called Valence electrons.
See, the 8( 8 because the element have to complete it's octane) - number of valence electron in an element = Valence of the element.