Redox reactions

Introduction

“Redox” is a chemical process which involves two steps together: Reduction and Oxidation. Dioxygen (O2(g)) was historically the first identified oxidising agent, the term “oxidation” originally meant a reaction with oxygen that resulted in the formation of an oxide. Later, the word was expanded to embrace oxygen-like compounds that conducted parallel chemical processes. Eventually, the term was broadened to include any process that results in the loss of electrons as a result of a charge transfer.

The term “reduction” originally referred to the weight loss that occurs when a metallic ore, such as a metal oxide, is heated in order to extract the metal. To put it another way, the ore was “reduced” to metal. Antoine Lavoisier established that this loss of weight was caused by the loss of oxygen in the form of a gas in his experiments. Scientists then discovered that the metal atom gets electrons as a result of this process. The term “reduction” was later broadened to describe any process that results in an increase in the number of electrons present. Example is the formation of hydrogen fluoride.

Oxidation- Reduction reaction (redox)

The oxidation-reduction reaction is referred to as the redox reaction. A redox reaction is a chemical reaction in which atoms’ oxidation states change as a result of the reaction. Electron transfer is required, which means that if one chemical species gets electrons, then another chemical species must either donate or lose electrons. Those species from which an electron has been removed are referred to as being oxidised, whereas those species to which an electron has been added are referred to as being reduced. As an illustration, zinc displaces copper in aqueous solution of copper sulphate (copper sulphate).

Any chemical process in which the oxidation number of a participating chemical species changes is referred to as an oxidation-reduction reaction, often known as a redox reaction. There is a broad and diverse set of processes that fall under this category. There are many examples of oxidation-reduction reactions that are as ubiquitous and familiar as fire, rusting and dissolving of metals, the browning of fruit, and the processes of respiration and photosynthesis—all of which are essential life functions.

Oxidation reaction in brief

A chemical reaction in which oxygen or a more electronegative element is added to or removed from a substance is known as an oxidation reaction. Another definition of oxidation reactions states that it is defined as the addition of oxygen or the more electronegative element to or removal of hydrogen or the more electropositive element from a substance.

The term “rusting” is frequently used to refer to the process of oxidation. Not all substances that come into contact with oxygen, on the other hand, crumble into rust. For example, iron that has been exposed to oxygen will go through a deliberate burning process, which will result in rusting.

Reduction reaction in brief

At the same time, in a chemical reaction, reduction and oxidation take place side by side. Oxidation is defined as the loss of electrons in one material, while reduction is defined as the transfer of these lost electrons to another element. Reduction might involve molecules, atoms, or ions, depending on the sort of chemical reaction that is taking place. It is usual to encounter reduction reactions when working with acids and bases or in the course of other electrochemical activities. Reduction reactions are also essential in physiological reactions and in industrial processes.

Reduction processes, like oxidation events, are characterised by the gain of electrons as the end result. The reduction of any substance occurs when it gains an electron during a chemical reaction. In other words, the addition of hydrogen or a more electropositive element to a substance, or the removal of a more electronegative element or oxygen from a substance, is how the reduction reaction is described.

Redox reactions of metal ions

In the formation of hydrogen fluoride, an example of a redox reaction can be seen. A few examples of redox reactions that occur in everyday life are discussed, including photosynthesis, degradation, respiration, biological processes, corrosion/rusting, combustion, and batteries. Provided as fuel for the organism’s metabolic phase Chlorophyll increases the sensitivity of the photosynthesis reaction to light.

Types of Redox Reaction

The major types of redox reaction are:-

1. Disproportionation Reaction
2. Combustion Reaction
3. Displacement Reaction
4. Decomposition Reaction
5. Combination Reaction

Applications of Redox Reaction in the Real World

In addition, the production of various key compounds is based on the electrolysis of water, which is in turn based on the redox reactions of water. Many compounds, such as caustic soda, chlorine, and other similar substances, are created by redox reactions.

Oxidation-reduction reactions are also used in the sanitization of water and the bleaching of materials. It is possible to protect the surfaces of many metals from corrosion by connecting them to sacrificial anodes, which are subjected to corrosion instead of the metals being protected. The galvanization of steel is a common example of this process in use today.

It is necessary to use the oxidation process in the industrial manufacture of cleaning goods. The oxidation reaction of ammonia results in the production of nitric acid, which is a component of many fertilisers.

It is a procedure that employs redox reactions to coat an object with a thin layer of a particular substance. • The process of electroplating is utilised in the manufacture of gold-plated jewellery. Redox processes are used to extract several metals from their ores, and they are quite effective. In the presence of reducing agents, metal sulphides are melted, which is an example of this type of reaction.

Conclusion

The most important source of oxidation is oxygen, and as a result, redox processes, also known as oxidation-reduction reactions, are the primary cause of food spoilage.