Nuclear Binding Energy
The energy that would be required to separate a nucleus completely into its individual protons and neutrons.
Formula / equation
E = Δm c²
Unit
MeV
In depth
Binding energy appears as the mass defect, since the assembled nucleus weighs less than its parts. It is the energy released when the nucleus forms and the reason nuclear processes liberate so much more energy than chemical ones — millions of electronvolts rather than a few.
Examples in the real world
A helium-4 nucleus has a binding energy of 28.3 MeV, about seven million times a typical bond energy.