BE BE_products BE_reactants BE_Rb   93 BE_Cs   140 BE_U   235 809  MeV 1176  MeV 1786  MeV 199  MeV 1 0 n 235 92 U 236 92 U 140 55 Cs 93 37 Rb 3 1 0 n Mass  difference Mass  of  Reactants Mass  of  Products 236.052589 amu 235.85208 amu 0.200509 amu E_Inst 0.020059 amu 931.5  MeV amu 186.8  MeV Atomic and Nuclear Physics DOE-HDBK-1019/1-93 ENERGY RELEASE FROM FISSION Rev. 0 Page 59 NP-01 The energy released will be equivalent to the difference in binding energy (   BE) between the reactants and the products. The energy liberation during the fission process can also be explained from the standpoint of the conservation of mass-energy.  During the fission process, there is a decrease in the mass of the system.  There must, therefore, be energy liberated equal to the energy equivalent of the mass lost in the process.  This method is more accurate than the previously illustrated method and is used when actually calculating the energy liberated during the fission process. Again, referring to the "typical" fission reaction. E    , the instantaneous energy, is the energy released immediately after the fission process.  It Inst is equal to the energy equivalent of the mass lost in the fission process.  It can be calculated as shown below. Mass of the Reactants Mass of the Products U 235.043924 amu Rb   92.91699 amu 235 92 93 37 n    1.008665 amu Cs 139.90910 amu 1 0 140 55 3 ( n)      3.02599 amu   1 0 236.052589 amu 235.85208 amu This mass difference can be converted to an energy equivalent.