Reduction: Reduction is defined as the addition of hydrogen, removal of oxygen, addition of metallic element or addition of electrons.
Eg. Reduction of ethyl bromide
Nitrobenzene can be reduced to aniline by using Fe + HCl
Calcination: is defined as the process by which Ore is subjected to the action of heat at high temperature in the absences of air.
Reaction involved in calcinations of lime stone:
Nitration is defined as unit process where one or more nitro groups are introduced into an organic compound. OR It is the reaction with nitrating mixture to introduce nitro(NO2) group into an organic compound. Nitrating mixture is a mixture of con. Sulfuric acid and con. Nitric acid.
Nitrating mixture is used in nitration reaction.