Here's an example of the graphs I am currently studying. http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/imgnuk/bcurv.gif I think I have a fundamental misunderstanding of its meaning that I would love to get past. I understand that Fe-56 is the most stable nucleus (although I'm not sure why) and that nuclei above that mark are more likely to fission and nuclei below Fe in regard to their atomic number are more likely to fuse in order to achieve the thermodynamically favorable, very stable Fe nucleus. I understand that binding energy is the energy required to break apart the nucleus into its constituent nucleons. Questions: 1) This seems counterintuitive, and not in the good way, 'He' for example has a much lower binding energy than 'U', why is this the case. To me, 'He' having a lower bonding energy means that it requires less energy to break apart and is thus not as strongly held together and would be more likely to fission rather than fuse. Visa versa for 'U', it has a high bonding energy, so it is strongly held together, so it should not readily fission. This is not what is observed, what is the misconception I'm experiencing, please explain and expand. 2) What does it mean to have a binding energy per nucleon in the first place, binding energy is the energy required to break the entire nucleus apart, how can we interpret binding energy based on its value per nucleon. Please feel free to lend any other insight that might improve my comprehension of this topic! Thank you.