Question

Methane reacts with chlorine in the presence of sunlight. What is the name of this reaction?

• A. substitution reaction
• B. acid base reaction
• C. addition reaction
• D. double displacement reaction

Answer 1

The correct option is A substitution reaction

Methane reacts with chlorine in the presence of sunlight, it is an example of a substitution reaction is also called halogenation. When chlorine gas $(Cl-Cl)$ is irradiated, some of the molecules are split into two chlorine radicals $\left(Cl\right)$ whose free electrons are strongly nucleophilic. One of them breaks a weak $C-H$ covalent bond and grabs the liberated proton to form the electrically neutral $HCl$. The other radical reforms a covalent bond with the $C{H}_3$to form $C{H}_{3}Cl.$
$C{H}_4+C{l}_2\stackrel{Sunlight}{\to }C{H}_{3}Cl+HCl$
$C{H}_{3}Cl+C{l}_2\stackrel{Sunlight}{\to }C{H}_{2}C{l}_2+HCl$
$C{H}_{2}C{l}_2+C{l}_2\stackrel{Sunlight}{\to }CHC{l}_3+HCl$
$CHC{l}_3+C{l}_2\stackrel{Sunlight}{\to }CC{l}_4+HCl$
Option A is correct.