2004 AIPMT Haloalkanes and HaloarenesPolyhalogen Compounds: Chloroform Easy Question 50 of 55 in Haloalkanes and Haloarenes

Chloropicrin is obtained by the reaction of

A Nitric acid on chlorobenzene
B Chlorine on picric acid
C Nitric acid on chloroform
D Steam on carbon tetrachloride

The answer is C.

Solution

Chloropicrin is trichloronitromethane, $CCl_3NO_2$. It is used as a tear gas and an insecticide.
It is formed when chloroform is heated with concentrated nitric acid (nitration of chloroform):
$CHCl_3 + HNO_3 \rightarrow CCl_3NO_2 + H_2O$
So chloropicrin is obtained by the reaction of nitric acid on chloroform. (It can also be made from picric acid with bleaching powder, but not by chlorine alone.)

Concept Formation of chloropicrin

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55 questions from this chapter have appeared across 25 exam years.