The binding energy is what holds the nucleus together. As you might expect, the more nucleons present in an atom, the stronger the binding energy gets . A more useful measure of the strength of the binding energy is the binding energy per nucleon . This graph also indicates something about how much energy can be utilized by nuclear reactions. If we break heavy atoms into smaller ones, than the energy difference will be smaller than if we combine two lighter atoms together.
Fusion reactions produce more power than fission .
Nuclear fission is the breaking up of heavy atoms into lighter atoms, by bombarding the heavy atoms with appropriately energetic neutrons. 235 U and 239 Pu are the two nuclei commonly referred to in this process. It is this principle of a chain reaction upon which nuclear power and weapons are designed. 235 U. This is done by gaseous diffusion of UF 6 . Recall our discussions of gaseous diffusion from 101- the lighter the molecule, the faster it diffuses through space.