Question

Calculate the bond dissociation energy (in kJ/mol) of the C-H bond in methane (CH4) using the following given data:- Enthalpy of formation of methane (CH4) = -74.8 kJ/mol- Enthalpy of combustion of methane (CH4) = -890.4 kJ/mol- Enthalpy change for the breaking of all four C-H bonds in methane = 1665 kJ/mol.

Answer 1

To calculate the bond dissociation energy of a single C-H bond in methane, we need to find the energy required to break one C-H bond. We are given the enthalpy change for breaking all four C-H bonds in methane, which is 1665 kJ/mol. Since there are four C-H bonds in methane, we can divide the total enthalpy change by the number of bonds to find the bond dissociation energy for one C-H bond:Bond dissociation energy of one C-H bond =  Enthalpy change for breaking all four C-H bonds  /  Number of C-H bonds Bond dissociation energy of one C-H bond = 1665 kJ/mol / 4Bond dissociation energy of one C-H bond = 416.25 kJ/molTherefore, the bond dissociation energy of the C-H bond in methane is 416.25 kJ/mol.