Question

When chlorine is passed through warm benzene in presence of the sunlight, the product obtained is:
A. Benzotrichloride
B. Chlorobenzene
C. Gammexane
D. DDT

Answer 1

Hint: This is a type of chlorination reaction where the addition of chlorine is done at the benzene ring. One needs to analyze the given conditions in which the reaction is performed and guess the number of chlorine atoms that got replaced on the benzene molecule.

Complete step by step answer:
-First of all, let's see the reaction where chlorine is passed through warm benzene in presence of the sunlight which is as follows,

-When chlorine reacts with the warn benzene in presence of U.V. light i.e. sunlight then there is the addition of chlorine atom on each carbon atom in the benzene.
-There is also breaking of double bonds present between the two carbon atoms in the benzene ring and to fill up the valency there the addition of chlorine atom takes place at each carbon atom.
-The formation of benzene Hexa chlorine is done which is also called B.H.C. The common name for this compound is Gammexine.
-Therefore, in the reaction where the chlorine is passed through warm benzene in presence of the sunlight i.e. U.V. Light Gammexane is obtained as a product which shows option C as the correct choice of answer.

Note: In the above reaction sunlight is used as a catalyst that initiates the reaction to proceed further. Gammexine or B.H.C formed as a product is also used as an insecticide. Even though it is commonly called benzene hexachloride (B.H.C) the correct chemical name for this compound is hexachlorocyclohexane.