Question

What is the difference between valence shell electrons and valency ?

Answer 1

The combining capacity of an atom is called its valency. Actually it can be defined as the number of electrons that an atom may lose (or) gain during a chemical reaction (or) the number of electrons shared. Ex: In water molecule H₂O (H - O – H) Valency of Hydrogen is ‘ 1 ‘ (as it combines with Oxygen atom by one single bond) and valence electrons in Hydrogen = 1 Valency of Oxygen is ‘2’ (as it combines with two Hydrogen atoms by two bonds).but valence electrons in oxygen = 6 . ​​​The number of electrons in outermost shell (or) valency shell of an atom are called valence electrons.