question_answer

Iodine does not react with ethane though \[{{I}_{2}}\]  is more easily cleaved homolytically than the other halogens. Explain.

Answer:

                Bond dissociation enthalpy of \[{{I}_{2}}\] is less as compared to that of \[C{{l}_{2}}\]  and \[B{{r}_{2}}\]  which means that the homolysis of \[{{I}_{2}}\] is the easiest. However, \[HI\] formed in a reaction is a strong reducing agent and it makes the reaction reversible. Therefore, iodine does not reaction with ethane. \[\underset{\text{Ethane}}{\mathop{C{{H}_{3}}-C{{H}_{3}}+{{I}_{2}}}}\,\rightleftharpoons \underset{\text{Iodoethane}}{\mathop{C{{H}_{3}}-C{{H}_{2}}-I+HI}}\,\]