Q Value Of Alpha Decay — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Q-value of Alpha Decay Used to calculate the energy released during alpha decay in nuclear physics. Apply the principle of conservation of mass-energy. Total Energy before decay = Total Energy after decay. E initial = m parent c 2. E final = m daughter c 2 + m c 2 + Q (kinetic energy of products). Solve for Q: Q = (m parent - m daughter - m )c 2. Q > 0 for spontaneous radioactive decay. The system is assumed to be isolated. Masses must be rest masses. Confusing nuclear mass with atomic mass (though for alpha decay, neutral atomic masses can often be used as electron masses cancel). Forgetting to square the speed of light (c 2) when converting mass defect to energy. Mixing units: using 'u' (atomic mass units) without converting to kg or using the 931.5 MeV/c 2 conversion factor.