To calculate the bond dissociation energy for the C-H bond in methane, we can use the following combustion reaction:CH4 g + 2 O2 g CO2 g + 2 H2O l The heat of combustion of methane is -890 kJ/mol, which is the enthalpy change for this reaction. We can use Hess's Law to determine the bond dissociation energy. First, we need to find the enthalpy of formation of methane Hf CH4 .We know the enthalpy of formation of CO2 and H2O, and the heat of combustion of hydrogen. We can use these values to find the enthalpy of formation of methane using the following equation:Hc CH4 = Hf products - Hf reactants -890 kJ/mol = [Hf CO2 + 2Hf H2O ] - [Hf CH4 + 2Hf O2 ]Since the enthalpy of formation of O2 is zero it is in its standard state , the equation becomes:-890 kJ/mol = [-393.5 kJ/mol + 2 -285.8 kJ/mol ] - Hf CH4 Now, we can solve for the enthalpy of formation of methane:Hf CH4 = -393.5 kJ/mol - 2 -285.8 kJ/mol + 890 kJ/molHf CH4 = -393.5 + 571.6 + 890Hf CH4 = 1068.1 kJ/molNow that we have the enthalpy of formation of methane, we can calculate the bond dissociation energy for the C-H bond. Methane has four C-H bonds, so we can write the following equation:Hf CH4 = 4 * Bond dissociation energy C-H Now, we can solve for the bond dissociation energy:Bond dissociation energy C-H = Hf CH4 / 4Bond dissociation energy C-H = 1068.1 kJ/mol / 4Bond dissociation energy C-H 267.03 kJ/molTherefore, the bond dissociation energy for the C-H bond in methane is approximately 267.03 kJ/mol.