The standard enthalpy of formation `(Delta_(f)H^(@))` at `298K ` for methane `(CH_(4(g)))` is `-74.8kJ mol^(-1)`. The additional information required to determine the average energy for `C-H` bond formation would be `:`A. The dissociation energy of hydrogen molecule, `H_(2)`B. The dissociation energy of `H_(2)` and enthlpy of sublimation of carbonC. Latent heat vaporisation of methaneD. The first four ionisation energies of carbon and electron gain enthalpy of hydrogen

The standard enthalpy of formation `(Delta_(f)H^(@))` at `298K ` for m

1.	The standard enthalpy of formation `(Delta_(f)H^(@))` at `298K ` for methane `(CH_(4(g)))` is `-74.8kJ mol^(-1)`. The additional information required to determine the average energy for `C-H` bond formation would be `:`A. The dissociation energy of hydrogen molecule, `H_(2)`B. The dissociation energy of `H_(2)` and enthlpy of sublimation of carbonC. Latent heat vaporisation of methaneD. The first four ionisation energies of carbon and electron gain enthalpy of hydrogen
Answer» Correct Answer - B `C+2H_(2)rarrCH_(4)` `Delta_(f)H^(@)=[e_(C(Srarrg))+2xxe_(H-H)-4xxe_(C-H)]`

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