The standard enthalpy of formation (Delta_f H | vedclass

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(C) To calculate the average enthalpy of a $C-H$ bond in methane,we use the Born-Haber cycle approach based on the reaction: $C_{(graphite)} + 2H_{2(g

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The dissociation energy of $H_2$ and enthalpy of sublimation of carbon (graphite).

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(C) To calculate the average enthalpy of a $C-H$ bond in methane,we use the Born-Haber cycle approach based on the reaction: $C_{(graphite)} + 2H_{2(g)} 	o CH_{4(g)}$.To find the bond dissociation energy of $C-H$,we need to convert the reactants into gaseous atoms:$(i)$ The enthalpy of sublimation of carbon: $C_{(graphite)} 	o C_{(g)}$$(ii)$ The dissociation energy of the hydrogen molecule: $H_{2(g)} 	o 2H_{(g)}$By knowing these values,we can calculate the total energy required to atomize the reactants and then relate it to the formation enthalpy to find the average $C-H$ bond energy.

The standard enthalpy of formation $(\Delta_f H^o_{298})$ for methane,$CH_4$ is $-74.9 \ kJ \ mol^{-1}$. In order to calculate the average energy given out in the formation of a $C-H$ bond from this,it is necessary to know which one of the following?

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