Question

Identify the reducing agent in the following reactions.
A. $4N{H_3} + 5{O_2} \Rightarrow 4NO + 6{H_2}O$
B. ${H_2}O + {F_2} \Rightarrow HF + HOF$
C. $F{e_2}{O_3} + 3CO \Rightarrow 2Fe + 3C{O_2}$
D. $2{H_2} + {O_2} \Rightarrow 2{H_2}O$

Answer 1

Hint:Reducing agent which is also called as a reductant is an element or a compound that loses or donates an electron to an electron recipient or an oxidizing agent in a redox chemical reaction. A reducing agent is thus oxidized when it loses electrons in the redox reaction. Reducing agents reduce the oxidizing agents. Oxidizers help to oxidize the reducing agents.

Complete step by step answer:
A reducing agent is the element or compound which reduces others and oxidizes itself. The reduction of a substance is done by addition of hydrogen or removal of oxygen atoms. Let us find the reducing agent in the given reactions one by one. Before finding the reducing agent, we need to specify some points for defining the reducing agent in the reaction.
(i) If there is an addition of hydrogen in compound A because of compound B, the compound B is known as the reducing agent.
(ii) If there is an addition of oxygen in the compound C because of the compound D, the compound D is known as the oxidising agent.
A. $4N{H_3} + 5{O_2} \Rightarrow 4NO + 6{H_2}O$
In the above reaction, ammonia (\[N{H_3}\]) is the reducing agent as it is being oxidized by oxygen (\[{O_2}\]) to form nitric oxide (\[NO\] ) and water (\[{H_2}O\] ).
B. ${H_2}O + {F_2} \Rightarrow HF + HOF$
In the above reaction, fluorine (\[{F_2}\]) is the reducing agent as it is being oxidized by water (\[{H_2}O\]) to form hydrogen fluoride (\[HF\] ) and hypofluorous acid (\[HOF\] ).
C. $F{e_2}{O_3} + 3CO \Rightarrow 2Fe + 3C{O_2}$
In the above reaction, iron (III) oxide (\[F{e_2}{O_3}\]) is the reducing agent as it is being oxidized by carbon monoxide (\[CO\]) to form hydrogen iron (\[Fe\] ) and carbon dioxide (\[C{O_2}\] ).
D. $2{H_2} + {O_2} \Rightarrow 2{H_2}O$
In the above reaction, hydrogen (\[{H_2}\]) is the reducing agent as it is being oxidized by oxygen (\[{O_2}\]) to form water.

Note:From the above reactions, it is also observed that some reactions undergo both oxidation and reduction reactions simultaneously and such types of reactions are known as redox reactions. In this type of reaction, there is a simultaneous addition or removal of electrons between the reactants and the products.