1. The problem statement, all variables and given/known data The heat of atomization of methane and ethane are 360kJ/moo and 620kJ/mol, respectively. The longest wavelength of light capable of breaking the C-C bond is (Avogadro number = 6.02 x 1023, h= 6.62 x 1034J s 2. Relevant equations E = hν = hc/λ 3. The attempt at a solution I think we should consider energy of ethane only as it only has C-C bond. What is the use of methane energy?