mass number: Quick Facts

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Facts

Also Known As	nucleon number • atomic mass number

Photos

average binding energy per nucleon as a function of the mass number

A scientific graph plots average nuclear binding energy per nucleon (in MeV) against atomic mass number, showing a sharp rise at low mass numbers, peaking near iron (Fe), then gradually declining for heavier elements. Key isotopes are labeled along the curve.

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Topics

atom radioactivity magnetic resonance fundamental force atomic weight mole valence atomic radius binding energy nuclear reaction atomic mass