Question

Identify the reducing agent in the following reaction:
$4N{H_3} + 5{O_2} \to 4NO + 6{H_2}O$

Answer 1

In a redox reaction, the reducing agent is defined as the reactant species which donates its electrons to other reactant species and gets oxidized during the redox reaction. The reducing agent is also known as reducer or reductant.

Complete step by step answer:
When oxidation reaction and reduction reaction takes place simultaneously then redox reaction takes place. Redox reaction is defined as the reaction where transfer of electrons takes place between the two reactive species to form the product.
When the reactant molecule loses its electron to form the product, then the reaction is called an oxidation reaction. In oxidation increase in oxidation state of the atom takes place from the reactant to the product.
When the reactant molecule gains electrons to form the product, then the reaction is called a reduction reaction. In reduction, decrease in oxidation state of the atom takes place from the reactant to the product.
The reducing agents are those species which donate their electrons to other species. The reducing agent is oxidized when it loses its electrons in the redox reaction.
The oxidizing agents are those species which accept the electrons from other species. The oxidizing agent oxidises the other species and itself gets reduced during the redox reaction.
The given reaction is shown below.
$4N{H_3} + 5{O_2} \to 4NO + 6{H_2}O$

So, In this reaction, the ammonia is a reducing agent as it donates its electrons to oxygen to form nitric oxide.

Note: The oxidizing agent is also known as oxidant or oxidizer. The oxygen is the oxidizing agent as it accepts electrons from ammonia. The oxygen molecule oxidises ammonia and itself gets reduced during the redox reaction.