Mass Defect Calculator — Formule
## Nuclear Mass Defect
The mass defect is the difference between the total mass of individual nucleons and the actual mass of the assembled nucleus.
### Formula
**delta_m = (Z × m_p + N × m_n) - M_atom**
where m_p = 1.007276 u (proton), m_n = 1.008665 u (neutron), and M_atom is the measured atomic mass. The mass defect is converted to binding energy via E = delta_m × 931.494 MeV/u.
The mass defect is the difference between the total mass of individual nucleons and the actual mass of the assembled nucleus.
### Formula
**delta_m = (Z × m_p + N × m_n) - M_atom**
where m_p = 1.007276 u (proton), m_n = 1.008665 u (neutron), and M_atom is the measured atomic mass. The mass defect is converted to binding energy via E = delta_m × 931.494 MeV/u.
Exemple Résolu
Fe-56: Z=26, N=30, measured mass = 55.9349 u.
- Expected mass = 26 × 1.007276 + 30 × 1.008665
- Expected = 26.1891 + 30.2600 = 56.4491 u
- Mass defect = 56.4491 - 55.9349 = 0.5142 u
- BE = 0.5142 × 931.494 = 479.1 MeV