Oxidized

What is the meaning of oxidised?

A substance is oxidised when it undergoes the process of oxidation. I.e the addition of oxygen or any electronegative elements or the removal of hydrogen or any electropositive element.

The most common example of oxidising is rusting: oxygen interacts with iron molecules to produce the new iron oxide molecules, better known as rust. There are other types of oxidising too, such as how the oxygen in our bodies is used to break down sugars. Oxidising is a type of chemical reaction.

Table of contents

• What is an oxidising agent?
• Oxidised by addition of oxygen
• Oxidised by addition of electronegative element
• Oxidised by removal of hydrogen
• Oxidised by removal of electropositive element
• Oxidised by loss of electron
• FAQs

What is an oxidising agent?

An oxidising agent (often referred to as an oxidiser or an oxidant) is a chemical species that tends to oxidise other substances. Or a substance which brings oxidation is known as the oxidising agent. It causes an increase in the oxidation state of the substance by making it lose electrons. Common examples of oxidising agents include halogens (such as chlorine and fluorine), oxygen, and hydrogen peroxide (H₂O₂).

Oxidised by addition of oxygen

In the process of oxidation by the addition of oxygen, the substance which reacts with oxygen gets oxidised to form oxide.

Examples

(i) 2Mg + O₂ → 2MgO

Here oxygen acts as an oxidising agent, and in presence of oxygen magnesium gets oxidised to form magnesium oxide.

(ii) S + O₂ → SO₂

Here sulphur is oxidised to form sulphur dioxide in reaction with oxygen.

(iii) Na₂SO₃ + H₂O₂ → Na₂SO₄ + H₂O

Here sodium sulfite is oxidised to form sodium sulfate and H₂O₂ acts as the oxidising agent.

Oxidised by addition of electronegative element

In this process of oxidation by the addition of electronegative elements, some substances get oxidised by reacting with electronegative elements like S, Cl, F etc.

Examples

(i) Fe + S → FeS

Here Iron gets oxidised in the presence of sulphur to form iron sulphide. S acts as an oxidising agent.

(ii) 2Fe + 3F₂ → 2FeF₃

Here iron gets oxidised in the presence of fluorine.

(iii)SnCl₂ + Cl₂ → SnCl₄

Here stannous chloride gets oxidised to form stannic chloride.

Oxidised by removal of hydrogen

In this process of oxidation, a substance gets oxidised by removing its hydrogen atom.

Examples:

(i) H₂S + Cl₂ → 2HCl + S

Here H₂S is oxidised by the loss of its hydrogen form S.

(ii) 4HI + O₂ → 2H₂O + 2I₂

Here HI is oxidised by loss of itsHere HI is oxidised by loss of its hydrogen form I₂.

(iii) 4HCl + MnO₂ → MnCl₂ + 2H₂O + Cl₂

Here HI is oxidised by the loss of its hydrogen form I₂.

Oxidised by removal of electropositive element

In the process of oxidation, a substance gets oxidised by removing its electropositive elements.

(i) 2KI + H₂O₂ → KOH + I₂

Here KI is oxidised by loss of electropositive element (K) form I₂.

(ii) 2KI + Cl₂ → KCl + I₂

Here KI is oxidised by loss of electropositive element (K) form I₂.

Oxidised by loss of electron

In this process of oxidation, A substance is oxidised by loss of one or more electrons. In this process oxidation state of oxidant increases.

Examples:

(i) Na → Na⁺ + e

Here sodium (Na) gets oxidised by loss of one electron from Na⁺ .

(ii) Zn → Zn²⁺ + 2e

Here Zinc(Zn) gets oxidised by loss of two electrons from Zn²⁺ .

(iii) Fe²⁺ → Fe³⁺ + e

Here Fe²⁺ gets oxidised by loss of one electron from Fe³⁺ .

Note: A substance which undergoes oxidation, acts as a reducing agent while a substance, which undergoes reduction, acts as an oxidising agent.