Drag along the binding-energy-per-nucleon curve. Everything climbs toward the iron peak near A = 56: light nuclei release energy by fusing, heavy nuclei by splitting. The presets show each reaction’s energy and the mass it converts via E = Δm·c².
Binding energy / nucleon at A = 30
8.47 MeV
of ~8.79 MeV at the Fe-56 peak
Mass number A30
Energy-releasing direction
Fusion releases energy
Combining light nuclei climbs toward iron.
Selected reaction E = Δm·c²
2H + 3H 4He + n
17.6 MeV
2.819 × 10-12 J
Δm = 0.01889 u = 3.137 × 10-29 kg
c = 299,792,458 m/s · 1 u = 931.494 MeV/c² = 1.66054 × 10-27 kg · 1 MeV = 1.602 × 10-13 J
Tip: slide past A ≈ 56 and watch the direction label flip from fusion to fission.