Concept of Valency Explained
The different orbitals (shells) in which electrons are grouped in atoms are denoted by the letters K, L, M, N, and so on. Valence electrons are those found in the outermost orbit or shell of an atom. Because the outermost orbit often contains more energy than the electrons found in other orbits, the valence electrons participate in every chemical reaction.
The Bohr-bury theory predicts that an atom’s outermost orbit will contain up to 8 electrons. However, very little to no chemical activity in the specific element is shown if the outermost orbit is completely filled. Their capacity for merging is reduced to almost nothing.
Noble gases are least reactive because their outermost orbit is entirely filled, which explains why. The ability of other elements to form noble gas configurations, however, determines how reactive they are. It will also assist in figuring out an atom’s valency.
Note: Learn more about Valence Bond Theory by visiting the attached link.
Valency
Valency of an element is a measure of an atom’s ability to combine with other atoms to create molecules or chemical compounds. The characteristics of an element that indicate how many more atoms can join one of its atoms in a covalent bond are known as valence, or valency, in chemistry. The term, which was first used in 1868, is used to represent both the broad potential of combining an element and the numerical value of the power of combining. Since the majority of bonds are created by the interchange of valence electrons, valence is defined as the number of electrons. The valence electrons determine what valences are and what their meaning is in chemistry.