The bond enthalpy of CH4, also known as methane, refers to the average amount of energy required to break one mole of CH4 molecules into its constituent atoms in the gas phase. The bond enthalpy values are typically expressed in kilojoules per mole (kJ/mol).
The bond enthalpy of CH4 can vary slightly depending on the specific conditions and measurement techniques used. However, as an approximation, the bond enthalpy of the carbon-hydrogen (C-H) bonds in methane is around 413 kilojoules per mole (kJ/mol). It's worth noting that this value represents the average energy required to break any of the four C-H bonds in a methane molecule.
It's important to keep in mind that bond enthalpies are average values and can vary depending on factors such as molecular environment, molecular geometry, and the presence of neighboring atoms or functional groups. Additionally, bond enthalpies are not always equal when measured in different compounds due to the influence of other atoms or groups on the bond strength.