Question

(a) The substance which loses electrons is called reducing agent.
(b) The substance which gains electrons is called an oxidizing agent.
Find out which is a true or false statement.
[A] (a) is true, (b) is false.
[B] (a) is false, (b) is true.
[C] Both are true.
[D] None of these.

Answer 1

Hint: The agents that reduce others substances are reducing agents and the agents that oxidise other substances are oxidising agents. Oxidation causes loss of electrons and reduction causes gain of electrons.

Complete answer:
We often come across the term oxidation and reduction in chemistry.
We can define these terms in various ways but generally the term oxidation is used for the gain of oxygen and reduction is used for the loss of oxygen. We can understand this better by taking an example. Let us take the following reaction-

     \[F{{e}_{2}}{{O}_{3}}+3CO\to 2Fe+3C{{O}_{2}}\]

Here, in iron (III) oxide, Iron is in +3 oxidation state and it is reduced to give us 2 moles of iron where the oxidation number is 0 and carbon monoxide is oxidised to give us carbon dioxide.
A compound which undergoes oxidation itself to reduce some other compound is known as a reducing agent and a compound which undergoes reduction itself to oxidise some other compound is known as an oxidising agent.
In simple words, we can write that an oxidising agent is an agent that oxidises something else and a reducing agent is a substance which reduces something other compound.
We know that a substance which undergoes oxidation loses electrons and a substance which undergoes reduction gains electrons. Therefore, if we want to write the above definition in terms of electrons, we can write that-
An oxidising agent will gain electrons because it undergoes reduction itself and a reducing agent will lose electrons because it undergoes oxidation itself.
So, the correct answer is “Option C”.

Note: Bronsted acids like sulphuric acid, chromic acid etc. are good examples of oxidising agents as they have an acidic proton which can be reduced to hydrogen gas. Lithium is a strong reducing agent and lithium aluminium hydride is used in various organic reactions for reduction.