Nuclear Stability: Why Some Atoms Last Forever

Nuclear stability depends on the balance between protons and neutrons.
Too many or too few neutrons make a nucleus unstable and radioactive.
Stable nuclei resist decay and can last for billions of years.
Magic numbers of nucleons (like 2, 8, 20, 28, 50, 82, 126) boost stability.
The strong nuclear force holds protons and neutrons tightly together.
Lighter elements need nearly equal protons and neutrons to stay stable.
Heavy elements require extra neutrons to counter proton repulsion.
The most stable nucleus is iron-56, with exceptionally high binding energy.
Unstable isotopes shed energy by emitting radiation until they reach stability.
Nuclear stability shapes the abundance of elements across the universe.