11th Class Chemistry Hydrocarbons / हाइड्रोकार्बन Question Bank 11th CBSE Chemistry Hydrocarbons

  • question_answer
    An oxidising agent is needed in the iodination of methane but not in the chlorination or bromination. Assign reason.

    Answer:

                    In the iodination of methane, \[H-I\] is also formed as the product along with iodomethane. Since it is a strong reducing agent, it reduces iodomethane back to methane and makes the reaction reversible. In order to destory \[HI\], oxidising agent like \[HI{{O}_{3}}\] (or\[HN{{O}_{3}}\]) is needed. But HCl and HBr formed in the chlorination and bromination reactions of methane are not in a position to react with the mono substituted product (i.e., \[C{{H}_{3}}-Cl\] and \[C{{H}_{3}}-Br\]) since they are comparatively weak reducing agents. Therefore, no oxidising agent is needed for these reactions. \[\underset{\text{Methane}}{\mathop{C{{H}_{4}}}}\,+{{I}_{2}}\rightleftharpoons C{{H}_{3}}I+HI\]  \[5HI+HI{{O}_{3}}\xrightarrow[\,]{\,}\,3{{H}_{2}}O+3{{I}_{2}}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner