Binding energy

Binding energy is the mechanical energy required to disassemble a whole into separate parts. A bound system has a lower potential energy than its constituent parts; this is what keeps the system together. The usual convention is that this corresponds to a positive binding energy.In general, binding energy represents the mechanical work which must be done in acting against the forces which hold an object together, while disassembling the object into component parts separated by sufficient distance that further separation requires negligible additional work.Electron binding energy is a measure of the energy required to free electrons from their atomic orbits.
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Noun
1. the energy required to separate particles from a molecule or atom or nucleus; equals the mass defect
(synonym) separation energy
(hypernym) energy

The energy equivalent of the mass defect of an atomic nucleus. The energy required to separate entities (a relatively great distance). The energy to pull an outer electron from an atom is of the order of a few electron volts (eV) and that needed to eject a proton or neutron from most atomic nuclei is around 7 million electron volts (MeV). If the reverse takes place, that is, a particle is captured the binding energy is released. The energy in all cases, is either comes from, or turns into, mass according to the energy-mass equivalence equation of Einstein .

The minimum energy required to separate a nucleus into its component neutrons and protons.

ENERGIA DI LEGAME [FISICA NUCLEARE]