A hypothetical atom with negligible kinetic energy has a mass of 227 amu. It undergoes a beta decay. The remaining atom has atomic mass 226.7 amu. What is the kinetic energy and/or wavelength (whichever is more appropriate) of the emitted particle, assuming that the kinetic energy of the remaining atom is negligible? How much energy would be released by the decay of a mole of these atoms? Note that the mass of a helium nucleus is about 4.001 amu and the mass of an electron about .00055 amu, where an amu is approximately 1.66 * 10^-27 kg?
The change in atomic mass is approximately 227 amu - ( 226.7 amu + .00055 amu) = .299453 amu, or about .4970921 * 10^-27 kg.
This corresponds to an energy of
A mole of these nuclei would constitute 6.02 * 10^23 nuclei, each releasing 4.473829 * 10^-13 Joules. The total energy released would therefore be