Hydrocarbons Question 279
Question: Which of the following is not formed by the reaction of $ Cl_2 $ on $ CH_4 $ in sunlight [AIIMS 1987]
Options:
A) $ CHCl_3 $
B) $ CH_3Cl $
C) $ CH_3CH_3 $
D) $ CH_3CH_2CH_3 $
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Answer:
Correct Answer: D
Solution:
$ CH_4\xrightarrow{Cl_2}CH_3Cl\xrightarrow{Cl_2}CH_2Cl_2\xrightarrow{Cl_2} $
$ CHCl_3\xrightarrow{Cl_2}CCl_4 $ .
Since this reaction takes place by free radical mechanism.
Hence, there is a possibility of formation of ethane.
$ \underset{\text{Methyl free radicals}}{\mathop{\overset{.}{\mathop{C}}H_3+\overset{.}{\mathop{C}}H_3}}\to \underset{Ethane}{\mathop{CH_3-CH_3}} $
$ CH_4\xrightarrow{Cl_2}CH_3Cl\xrightarrow{Cl_2}CH_2Cl_2\xrightarrow{Cl_2} $
$ CHCl_3\xrightarrow{Cl_2}CCl_4 $ .
Since this reaction takes place by free radical mechanism.
Hence, there is a possibility of formation of ethane.
$ \underset{\text{Methyl free radicals}}{\mathop{\overset{.}{\mathop{C}}H_3+\overset{.}{\mathop{C}}H_3}}\to \underset{Ethane}{\mathop{CH_3-CH_3}} $