Q-value of a nuclear reaction or decay (Q = (Σm_initial − Σm_final) c²)

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Q = (Σm_initial − Σm_final) c²

What each symbol means

SymbolWhat it stands for
QEnergy released to kinetic energy of products (if positive)
cSpeed of light
mRest masses with consistent convention (atomic or nuclear)

When to use this

Closed system; neglect small electron binding differences unless stated; products excited states reduce Q if not accounted.