Oxidation and Reduction-Redox Reactions

Introduction

There are several chemical reactions and interactions in the world of chemistry. One of the most important reactions and processes is the redox reaction.

In this module, we will study the notion of redox reactions, redox reaction balancing questions, and several other chemical words related to the issue of oxidation.

In chemistry, many chemical processes and reactions occur, which redox reaction is one of the most basic and important reactions and processes to occur. The process and concept of corrosion of metals that occur and which we see around us on a day-to-day basis on various metallic substances result from the redox reaction.

What is a Redox Reaction?

The reduction-oxidation process is called a redox reaction in chemistry. All redox reactions may be of two types, namely- reduction and oxidation. A redox reaction is also sometimes known as the Reduction-Oxidation process since it always involves both oxidation and reduction processes that happen simultaneously in the given chemical reaction. 

In a given chemical reaction, the reduced substance is referred to as the oxidising agent. In contrast, the substance that undergoes the process of oxidation is said to be the reducing agent. 

Examples of Redox Reactions

4Al (Aluminium) + 3O2 (Oxygen) → 2Al2O3 (Aluminium Oxide)

H2S (Hydrogen Sulphide) + Cl2 (Chlorine) → S (Sulphur) + 2HCl (Hydrochloric Acid)

2SO2 (Sulphur dioxide) + O2 (Oxygen) → SO3 (Sulphur trioxide)

Redox Reaction Balancing Questions

A redox reaction is a type of chemical reaction wherein the oxidation states of atoms change and electrons are transferred between the two reactants involved. It is an electron transport process that involves two reactions: reduction and oxidation. This reaction changes the oxidation states of the chemically reactive species, with one chemical substance losing electrons and the other chemical species acquiring electrons simultaneously.

Every element of life requires a sense of balance. Nothing in excess is beneficial for anyone, and things must always be balanced and proportionate. Reactions, too, must be balanced. The balancing of redox reactions is an important part of chemistry.

Types of Redox Reactions

• Decomposition Reaction
• Double Decomposition Reaction
• Combination Reaction
• Displacement Reaction
• Disproportional Reaction

Disproportional Reaction

A Disproportional Reaction is a reaction in chemistry where just one component from the reactants goes under oxidation and reduction.

For Example- 

Cl2 + 2NaOH → NaCl + NaClO + H2O. (Disproportion of Chlorine)

Displacement reaction

A Displacement Reaction is a chemical reaction when a single atom or a single ion from an atom in a given reaction is replaced by another ion or atom of a completely different element. A displacement reaction can be of four different types: Single Displacement Reaction, Double Displacement Reaction, Metallic Displacement, and Non-Metallic Displacement Reaction.

For Example- 

CuS04 + Zn → Cu + ZnSO4

AgNO3 + NaCl → AgCl + NaNO3

Combination Reaction

A Combination Reaction is a chemical reaction that is the exact opposite of a Decomposition Reaction. This chemical reaction is defined as a combination of a metallic substance and a non-metallic substance to give an ionic solid a product at the end of the reaction.

For Example-

C + O2 → CO2

The general formula for a chemistry combination reaction is-

X + Y → XY.

Decomposition Reaction 

A Decomposition Reaction is a chemical reaction in which a chemical compound is broken down into various sub compounds. This reaction is the opposite of a chemical Combination Reaction.

The general form for this equation can be written as AB → A + B.

For Example- 2NaH → 2Na + H2

A decomposition reaction is of three different types: Photolysis Decomposition Reaction that happens because of the presence of light, Thermal Decomposition Reaction that happens due to the application or presence of heat, Electrolytic Decomposition Reaction that happens because of the presence or passage or electricity.

Double Decomposition Reaction 

A Double Decomposition Reaction is a chemical reaction in which the process of change from one chemical atom or a substance into two or more new compounds takes place. A double replacement reaction, in simple terms, is defined as the occurrence when a positively charged ion is exchanged with another positively charged ion of a given molecule. A double decomposition reaction is the opposite of a combination reaction. They are further classified into two subtypes or reactions: Precipitation Reaction and Neutralisation Reaction.

Or 

A double replacement reaction occurs when two cations or anions swap places in a reaction to form two new compounds. In this reaction, A and B are cations that swap their ionic partnerships.

The general form of representation of a double decomposition reaction is-

AB + CD → AD + BC.

For Example- AgNO3 (aqueous) + NaCl (aqueous) → AgCl (milky white precipitate) + NaNO3 (aqueous)

Applications of Redox Reactions

1. Redox reactions are mainly carried out in the extractions of metals.
2. They are also used in Electrochemical Cells.
3. In acid-base titration, redox reactions are used for quantitative analysis.
4. Corrosion of metals. Metals get oxidised to form metallic oxides on their surfaces.
5. Bleaching- A way to remove the unwanted colours from clothes and fabric material. 

Conclusion

Redox Reaction plays an important role in chemistry and is one of the most important and basic concepts. In this article, we learnt about the various types of redox reactions and the applications of redox reactions.We can see redox reactions in our day to day life like rusting of iron.Redox reactions also play an essential role in the field of electrolysis.

This module can be very helpful for all the students who wish to appear for various examinations and competitive examinations.