Question

What is the difference between valency and oxidation numbers?

Answer 1

Difference between valency and oxidation number

Serial number	Valency	Oxidation number
1	"The combining power (or capacity) of an element is known as its valency."	“Oxidation number denotes the oxidation state of an element in a compound ascertained according to a set of rules formulated on the basis that electron pair in a covalent bond belongs entirely to a more electronegative element ”.
2	A valency is always a whole number.	The oxidation number of an element may be a fractional or whole number.
3	The valency of the pure element depends on the number of electrons present in the outer shell of an atom.	The oxidation number of the pure elements is always 0.
4	The valency of an element is generally fixed.	Oxidation number of an element may have different values.