What Is Difference Between Valency And Oxidation, Elements of the Periodic Table

Difference between Valency and Oxidation: Valency and oxidation are the topics of JEE Main 2025 Chemistry Syllabus . Valency is the number of Chemical bonds an atom can form. Oxidation is the number of elements in a chemical compound and is a measure of the degree of oxidation or reduction. Candidates can check the difference between Valency and Oxidation in the article below.

What is Valency?

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Important Facts For Valency of an Element

• The valency of an element is the number of electrons present in the outermost shell that can participate in a reaction.
• It depends on the group number of an element. Such as elements from the group numbers 1, 2, 13 and 18, the valency is often equal to the group number. For example, elements in group 1 have a valency of 1 and group 2 have a valency of 2 and so on. However, 17 and 18 groups are exceptions.
• The transition elements present in the periodic table can have variable valencies.
• The electronic configuration of an element also determines its valency. Elements lose or gain free electrons to achieve the stable noble gas configuration.
• Elements having 1, 2 and 3 electrons in their outermost shell donate their free electrons to achieve a noble gas electron configuration. They are generally metals.
• Elements having 5, 6, and 7 elements in their outermost shell generally accept the free electrons from the neighbouring elements to achieve the noble gas configuration. They are generally non-metals.

What is the Oxidation Number?

Important Facts for Oxidation Number

• Elemental form : An element's oxidation number is zero in its uncombined (elemental) state. The oxidation number of pure elemental oxygen (O2), for example, is zero.
• Monatomic ions: The oxidation number of a monatomic ion equals the ion's charge. For example, sodium (Na+) has an oxidation number of one, and chloride (Cl-) has an oxidation number of one.
• The sum of a compound's oxidation numbers is: The sum of the oxidation numbers of all the atoms in a neutral compound is zero. The sum of the oxidation numbers in an ion equals the ion's charge.
• Hydrogen has an oxidation number of +1 in the majority of compounds. Hydrogen, on the other hand, has an oxidation number of -1 in hydrides like NaH.
• Oxygen: The oxidation number of oxygen in most compounds is -2. There are some exceptions, such as peroxides (for example, H2O2), in which each oxygen has an oxidation number of -1.
• Fluorine has an oxidation number of -1 in all compounds.

Difference between Valency and Oxidation Number

Valency of the First 30 Elements of the Periodic Table