question_answer

Consider the reactions                 \[C(s)+2{{H}_{2}}(g)\to C{{H}_{4}}(g),\Delta H=-x\,kcal\]                 \[C(g)+4H(g)\to C{{H}_{4}}(g),\,\Delta H=-{{x}_{1}}\,kcal\]                 \[C{{H}_{4}}(g)\to C{{H}_{3}}(g)+H(g),\,\Delta H=+y\,kcal\]                 The bond energy of \[C-H\] bond is         [JIPMER 1997]

A)                 \[y\,kcal\,mo{{l}^{-1}}\]               

B)                 \[{{x}_{1}}\,kcal\,mo{{l}^{-1}}\]

C)                 \[x/4\,kcal\,mo{{l}^{-1}}\]          

D)                 \[{{x}_{1}}/4\,kcal\,mo{{l}^{-1}}\]