Question

Why are valence electrons named as such, rather than only electrons?

Answer 1

Valence electrons:

The electrons that are present in the outermost shell or valence shell of an atom are called as the valence electrons.

• Example: Number of electrons present in Sodium (Na) are 11.
• These electrons are arranged in the electronic configuration of Sodium as 2,8,1.
• The outermost electron i.e.; 1 is the valence electron of Sodium.

Valence electrons are named as such because out of all the electrons present in the atom, they help to know the valency of an atom.

• Valency: Valency is the combining capacity of an atom.
• With the help of valency, we can decide the number of electrons lost, gained or shared by an atom in order to attain the stable nearest noble gas configuration.
• Example: If the valence electrons in an atom are less than 4, then the valency= valence electron number
• If valence electrons are$\ge$4, then valency= 8- valence electron number