Example: For methane, the mean bond enthalpy is $415.9\mathrm{kJ}{\mathrm{mol}}^{-1}$, one-fourth the enthalpy of reaction for $$\mathrm{CH}{\phantom{A}}_4(\mathrm{g})⟶\mathrm{C}(\mathrm{g})+4\mathrm{H}(\mathrm{g})$$

Note: More commonly, tabulated mean bond energies (which are really enthalpies) are values of bond enthalpies averaged over a number of selected chemical species containing that type of bond, such as $414\mathrm{kJ}{\mathrm{mol}}^{-1}$ for $\mathrm{C}-\mathrm{H}$ bonds in a group of $\mathrm{R}{\phantom{A}}_3\mathrm{CH}$ ($\mathrm{R}=\mathrm{H}$, alkyl).