11. Conservation of Mass,       Charge, and Energy   Previous PageNext Page
       Mass and Energy: Nuclear Reactions

(We must include electrons in this calculation because 4.0026 amu is the mass of the helium-4 atom, not the nucleus.) This missing mass corresponds to 0.0305 x 931.4 MeV = 28.4 MeV of energy. If we could put together a helium atom directly from two neutrons, two protons, and two electrons, then 28.4 MeV of energy would be given off for every atom formed:


Compared to common chemical reactions, this is an enormous quantity of energy. Since 1 electron volt per atom is equivalent to 23.06 kcal per mole,

= 655,000,000 kcal mole-1

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