Redox reactions are oxidation-reduction chemical reactions in which the reactants undergo a change in their oxidation states. The term ‘redox’ is a short form of reduction-oxidation. All the redox reactions can be broken down into two different processes – a reduction process and an oxidation process.

The oxidation and reduction reactions always occur simultaneously, such class of chemical reactions was named as the redox reaction or Oxidation-Reduction Reaction. The substance getting reduced in a chemical reaction is known as the oxidizing agent, while a substance that is getting oxidized is known as the reducing agent.




What are Redox Reactions?
A redox reaction can be defined as a chemical reaction in which electrons are transferred between two reactants participating in it. This transfer of electrons can be identified by observing the changes in the oxidation states of the reacting species.


In the illustration provided above, it can be observed that the reactant an electron was removed from the reactant A, and this reactant is oxidized. Similarly, reactant B was handed an electron and was therefore reduced.

The loss of electrons and the corresponding increase in the oxidation state of a given reactant is called oxidation. The gain of electrons and the corresponding decrease in the oxidation state of a reactant is called reduction.

Electron-accepting species which tend to undergo a reduction in redox reactions are called oxidizing agents. An electron-donating species which tends to hand over electrons can be referred to as a reducing agent. These species tend to undergo oxidation. It can be noted that any redox reaction can be broken down into two half-reactions, namely the oxidation half-reaction and the reduction half-reaction.

When writing these half-reactions separately, each of them must be balanced in a way that all the electrons are accounted for.

Types of Redox Reactions
The different types of redox reactions are:

Decomposition Reaction
Combination Reaction
Displacement Reaction
Disproportionation Reactions