The bond dissociation energy BDE of a molecule is the energy required to break a specific chemical bond and form isolated atoms. In the case of methane CH4 , there are four C-H bonds. The BDE of a single C-H bond in methane is approximately 435 kJ/mol.Since there are four C-H bonds in methane, we need to multiply the BDE of a single C-H bond by the number of bonds:BDE CH4 = BDE C-H number of C-H bondsBDE CH4 = 435 kJ/mol 4BDE CH4 = 1740 kJ/molTherefore, the bond dissociation energy of a methane molecule CH4 is approximately 1740 kJ/mol, assuming that all the bonds are broken simultaneously and the products are isolated atoms.