Question

In $ Ca + {C_2} \to Ca{C_2} + {N_2} \to A $
Compound (A) is used as a/an:
(A) Fertilizer
(B) Dehydrating agent
(C) Oxidising agent
(D) Reducing agent

Answer 1

Hint: The reaction given is a synthesis reaction. Synthesis reaction is a reaction in which two compounds or elements react to form a single compound. A synthesis reaction is denoted as follows; $ A + B \to AB $

Complete Step by step solution
Any material, which is of natural or synthetic origin that is man-made or artificial, which when applied to soil or plant tissue supplies one or many plants essential nutrients for the growth of plants is known as a fertilizer. Example: calcium cyanamide, sodium nitrate, ammonium sulphate.
Dehydrating agent is a substance that dries or removes water molecules from a material or a compound and it itself absorbs the water. Example: aluminium phosphate, sulfuric acid, phosphorus pentoxide, phosphoryl chloride, calcium oxide.
Oxidising agent is a substance or a compound that tries to oxidise another compound or substance and itself gets reduced by gaining electrons, that is, it tends to bring oxidation and itself gets reduced. Example: oxygen, ozone, hydrogen peroxide, fluorine, chlorine, nitric acid.
Reducing agents are substances or compounds that try to reduce a substance or compound by losing electrons, that is it is a compound that brings reduction by oxidising itself. Example: earth metals, formic acid, oxalic acid and sulphate compounds.
Steps in which the reaction in question takes place are as follows,
Calcium reacts with carbon to form calcium carbide as seen in the reaction below,
 $ Ca + {C_2} \to Ca{C_2} + {N_2} $
Then calcium carbide reacts with nitrogen at high temperature to form calcium cyanamide which is used as a fertilizer.
 $ Ca{C_2} + {N_2} \to Ca{\left( {CN} \right)_2} + C $
Therefore, the correct answer is option A.

Note
The important sources of nutrients in mineral fertilizers are nitrogen, potassium and phosphate. This mineral helps plants to grow, stay healthy and flower well. Although excess use of inorganic fertilizer can pollute the underground water. The excessive use of fertilizers can also pollute the soil and can be toxic to humans.