A) The dissociation energy of the hydrogen molecule,\[{{H}_{2}}.\]
B) The first four ionisation energies of carbon.
C) The dissociation energy of \[{{H}_{2}}\] and enthalpy of sublimation of carbon (graphite).
D) The first four ionisation energies of carbon and electron affinity of hydrogen.
Correct Answer: C
Solution :
[c] To calculate average enthalpy of \[C-H\] bond in methane following informations are needed (i) dissociation energy of \[{{H}_{2}}\]i.e. \[\frac{1}{2}{{H}_{2}}(g)\xrightarrow{{}}H(g);\]\[\Delta H=x\] (suppose) (ii) Sublimation energy of \[C(\text{graphite})\] to \[C(g)\] \[C(\text{graphite})\xrightarrow{{}}C(g);\] \[\Delta H=y\] (Suppose) Given \[Ag\,\,\text{left}=\text{ }1.081.08=0\] \[C{{H}_{4}}(g);\]\[\Delta H=75\,kJ\,\,mo{{l}^{-1}}\]You need to login to perform this action.
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