Question

Benzene reacts with chlorine in presence of light to yield:
A. chlorobenzene.
B. trichlorobenzene.
C. tetrachlorobenzene.
D. benzene hexachloride.

Answer 1

Hint: To solve this question, we will use the concept of addition reaction. In organic chemistry, an additional reaction is an organic reaction in its simplest terms, where two or more molecules combine to form a greater one (the adduct).

Complete step by step answer:
Addition reactions are restricted to chemical compounds with multiple bonds, such as carbon-carbon double bonds (alkenes) or triple bonds (alkynes) molecules, and compounds with rings, which are often called unsaturation points.
Benzene addition reaction:
There are various problems with the addition of chlorine to benzene, creating multiple isomers of 1, 2, 3, 4, 5, 6-hexachlorocyclohexane. Benzene contains the hex halides, \[{C_6}{H_6}C{l_6}\] and \[{C_6}{H_6}B{r_6}\], which correspondingly, when processed by chlorine or bromine in the presence of sunlight. Via the free radical process, the additional reaction continues.
      

Hence, we can say that Benzene reacts with chlorine in presence of light to yield benzene hexachloride.
So, the correct answer is “Option D”.

Note: Hot benzene can also undergo an additional chlorine or bromine reaction in the presence of ultraviolet light (but without a catalyst present). The delocalisation of the ring is permanently disrupted and each carbon atom is replaced by a chlorine or bromine atom.