Which reagent will you use for the following reaction?
(a) Cl2/UV light (b) NaCl+H2SO4
(c) Cl2 gas in dark (d) Cl2 gas in the presence of iron in dark
Answer: (a) Cl2/UV light
The given reaction is a substitution reaction. It involves the replacement of 1∘ and 2∘ hydrogen of alkanes by chlorine. It occurs in presence of ultraviolet light or at high temperature.
The chlorination does not occur at room temperature in absence of light. In this reaction, light is absorbed by the chlorine molecule and activated chlorine initiates the reaction as follows