Question

Ethane is formed during the formation of chloromethane by chlorination of methane because:

• A. higher members of the hydrocarbons are generally formed during reactions
• B. two methyl free radicals may combine during chlorination to give ethane
• C. two chloromethane molecules react to form ethane
• D. chlorine free radical reacts with methane to give ethane.

Answer 1

Answer: (B)

two methyl free radicals may combine during chlorination to give ethane

Chlorination of methane is a free radical reaction. The free radicals formed during the reaction are $C{l}^{\bullet }$ and $C{H}_3^{\bullet }$. During the process if two methyl radicals collapse they form ethane. So, ethane is also formed as a byproduct.

$2{Cl}^{\bullet }\to {Cl}_2$

${H_{3}C}^{\bullet }+{Cl}^{\bullet }⟶C{H}_{3}Cl$

${H_{3}C}^{\bullet }+{H_{3}C}^{\bullet }⟶C{H}_3-C{H}_3$